Brain Teasers

04:47 New
Puzzles: 5 "easy"... and one impossible!! (with answers)
/ 5 views★★ For more broccoli puzzles stuffs... Subscribe to DB! ★★ The überchallenge is to solve the impossible parking lot question (brain teaser puzzle) at the end. But first warm up with some supposedly "easy" puzzles at the beginning. I hope you enjoy it and

03:50 New
Most People Fail!! (IQ test with answers)
/ 4 viewsMost people fail!! That's because they are either artists or scientists, but rarely both! See if you are smart enough to pass this Brain Test. Let me know in the comments! I hope you enjoy this brain challenge. I have combined visual memory with number me

03:28 New
95% Fail: 8 funny trick questions your friends will ALWAYS get wrong! (with answers)
/ 7 viewsThese are 8 awesome trick questions your friends will always get wrong! Guaranteed! :) I have picked these 8 funny brain teasers because I am sure that noone would get them right when asked spontaneously. See for yourself, whether you will get the right

05:18
Can you solve the rebel supplies riddle?  Alex Gendler
/ 29 viewsPractice more problemsolving at https://brilliant.org/TedEd/ Solution to Bonus Riddle: https://brilliant.org/tededmislabelledboxes/ You’re overseeing the delivery of supplies to a rebel base in the heart of enemy territory. To get past customs, all packa

07:45
The Monty Hall Problem  Christmas Lectures with Ian Stewart
/ 7 viewsIan Stewart explains the Monty Hall problem and its solution. Subscribe for regular science videos: http://bit.ly/RiSubscRibe The Monty Hall problem became infamous in the 1990s where newspaper columnist and puzzle solver Marilyn vos Savant offered a solu

01:34
Matchstick Dog
/ 221 viewsIf you solve this puzzle before the answer is given, you are the topdog in the class. Congratulations! SUBSCRIBE NOW http://www.youtube.com/subscription_center?add_user=CuriosityShow CONNECT WITH CURIOSITY Facebook ➤ http://www.facebook.com/CuriosityShow

01:30
LeftFacing Fish
/ 225 viewsDeane and Rob present a matchstick problem concerning leftfacing and rightfacing fish. See if you can solve the problem before the answer is given. SUBSCRIBE NOW http://www.youtube.com/subscription_center?add_user=CuriosityShow CONNECT WITH CURIOSITY Fa

04:12
Window Puzzles
/ 220 viewsDeane presents two window puzzles which depend on your ability to compare areas. SUBSCRIBE NOW http://www.youtube.com/subscription_center?add_user=CuriosityShow CONNECT WITH CURIOSITY Facebook ➤ http://www.facebook.com/CuriosityShow Twitter ➤ https://twit

05:39
Can You Solve A 5th Grade Problem From China? Find The Area Of ABCD
/ 130 viewsThanks to Eric from Miami for suggesting this problem and sending a solution! The diagram shows a quadrilateral ABCD with the values for some angles and the length of AB. Can you figure out the area of ABCD? Subscribe: https://www.youtube.com/user/MindYou

08:51
The Viral Balloon Puzzle  The REAL Answer Explained (Using Ph.D. Level Math)
/ 116 viewsThey say only geniuses can solve this puzzle, and this time they are correct. Thanks to all patrons! Special thanks to: Shrihari Puranik Yildiz Kabaran Kyle My blog post for this video https://wp.me/p6aMk82U Sources https://puzzling.stackexchange.com/que

05:08
Can you solve the Leonardo da Vinci riddle?  Tanya Khovanova
/ 169 viewsPractice more problemsolving at https://brilliant.org/TedEd/ Solution to Bonus Riddle: https://brilliant.org/tededautobiographical/ You’ve found Leonardo da Vinci’s secret vault, secured by a series of combination locks. Fortunately, your treasure map ha

06:13
The Broom Riddle (Solution) ft. Kurt Hugo Schneider part 3/3
/ 9 viewsVideo 1 with the bowl riddle: https://youtu.be/z0JpgEOLezY Video 2 with the broom and some bonus riddles: https://youtu.be/_34bYpxK_OE Check out Kurt's channel! http://www.youtube.com/kurthugoschneider Three tricky riddles! See if you can solve the 2s rid

06:24
Bowl Riddle Solution (Plus 2 BONUS riddles) ft. Kurt Hugo Schneider part 2/3
/ 21 viewsFirst video with Bowl Riddle and two other riddles: https://youtu.be/z0JpgEOLezY Check out https://wix.com/go/physicsgirl to get started on your website! See if you can solve the next two riddles in this video: (1) the silent round riddle (2) the broom ri

06:43
Can you solve the bowl riddle? ft. Kurt Hugo Schneider Part 1/3
/ 17 viewsAnswer to the bowl riddle: https://youtu.be/_34bYpxK_OE Three tricky riddles! See if you can solve (1) the bucket riddle (2) the clock puzzle (3) the bowl riddle! ft. musician and producer Kurt Hugo Schneider! Check out Kurt's channel! http://www.youtube.

03:21
Can You Solve A Puzzle That Fooled Richard Feynman?
/ 102 viewsWhat is the radius of the circle, in simplest terms involving a, b, and c? I read that even the great mind Richard Feynman made a mistake. Watch the video to learn the common mistake and what the correct answer is. Source Feynman story http://web.media.mi

05:48
What Is The Area? "You Should Be Able To Solve This"
/ 25 viewsThanks to Reio in Romania for emailing me this fun problem! What is the area? This puzzle was shared with the tagline "you should be able to solve this." Solution to 5th grade Chinese challenge problem https://youtu.be/OuJQaxZvlYs My blog post for this vi

05:52
Can You Solve The "MEANEST" SAT Test Question Ever?
/ 102 viewsOn the SAT exam, you have about 2 minutes to read and solve each math question. This one about averages can send you in a loop, unless you approach it systematically. In the video I also explain a shortcut to help you solve this type of problem quickly. S

05:13
Can you solve the rogue AI riddle?  Dan Finkel
/ 167 viewsPractice more problemsolving at https://brilliant.org/TedEd/ If you sign up for a FREE membership using the link above, Brilliant will email you the solution to the BONUS RIDDLE. A hostile artificial intelligence called NIM has taken over the world’s com

04:46
Can you solve the Mondrian squares riddle?  Gordon Hamilton
/ 78 viewsPractice more problemsolving at https://brilliant.org/TedEd/ Dutch artist Piet Mondrian’s abstract, rectangular paintings inspired mathematicians to create a twofold challenge. Can you solve the puzzle and get to the lowest score possible? Gordon

05:20
Can you solve the giant cat army riddle?  Dan Finkel
/ 71 viewsPractice more problemsolving at https://brilliant.org/TedEd/ Sign up to be emailed the solution to the bonus riddle: https://brilliant.org/tededm2s3/ The villainous Dr. Schrödinger has developed a growth ray and intends to create an army of giant cats to

11:11
THAT IS HOW YOU CAN CONFUSE YOUR MATH TEACHER AT SCHOOL
/ 55 viewsLearn how to draw prospective without a ruler, measure angles and figure out how many days there are in any given month with your hand! These and many others mindblowing Math tricks are in this video! There are some GREAT tricks for young mathematicians!

05:26
Can you solve the wizard standoff riddle?  Dan Finkel
/ 142 viewsPractice more problemsolving at https://brilliant.org/TedEd/ Sign up for free to receive the solution to the bonus riddle! You’ve been chosen as a champion to represent your wizarding house in a deadly duel against two rival magic schools. Your opponents

13:55
18 MATH RIDDLES THAT EVEN YOUR MATH TEACHER WILL FAIL
/ 222 viewsA great chance to challenge your math teacher! These 18 math riddles will trick and will make sweat even your math teacher: 00:14  Easy riddle to warm you up for the main brain workout. Kids solve this in seconds! 00:46  Riddle to test your ability to t
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13:43
17 FUN LOGICAL RIDDLES AND MATH TRICKS TO IMPRESS YOUR TEACHER
/ 125 viewsSimple and logical riddles for kids that will test the sharpness of your brain and awesome math tricks that will impress and embarrass your math teacher: 00:14  Cool riddles for kids and adults to warm up you for the main brain workout. 01:35  Tricky te

06:01
Can you solve the seven planets riddle?  Edwin F. Meyer
/ 421 viewsPractice more problemsolving at https://brilliant.org/TedEd/ Solution to the bonus riddle mentioned at the end: https://brilliant.org/TedEdTitanic/ Your interstellar police squad has tracked a group of criminals to a cluster of seven planets. Now you mus
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04:28
Can You Find The Hidden Animals?
/ 134 viewsCan You Find The Hidden Animals? ▶ Facebook: https://www.facebook.com/WOWQuiz ▶ Twitter: https://twitter.com/WOWQuizVideo 8 Cunning Tasks That Will Challenge Your Attention https://www.youtube.com/watch?v=sNePtfz0_k Only People With Perfect Vision Can Se

05:43
8 Cunning Tasks That Will Challenge Your Attention
/ 182 views8 Cunning Tasks That Will Challenge Your Attention ▶ Facebook: https://www.facebook.com/WOWQuiz ▶ Twitter: https://twitter.com/WOWQuizVideo Only People With Perfect Vision Can See These Images https://www.youtube.com/watch?v=tjVBZP1Y1r4 Impossible Hidden

04:02
Only People With Perfect Vision Can See These Images
/ 125 viewsOnly People With Perfect Vision Can See These Images ▶ Facebook: https://www.facebook.com/WOWQuiz ▶ Twitter: https://twitter.com/WOWQuizVideo Impossible Hidden Objects To Test Your Brain! https://www.youtube.com/watch?v=iAMxs8_vKEA What Do You See? 99% Fa

03:59
Impossible Hidden Objects To Test Your Brain!
/ 104 viewsImpossible Hidden Objects To Test Your Brain! ▶ Facebook: https://www.facebook.com/WOWQuiz ▶ Twitter: https://twitter.com/WOWQuizVideo What Do You See? 99% Fail! https://www.youtube.com/watch?v=D6_6H1tomKs 4 Logic Puzzles That Will Leave You Scratching Yo

04:03
What Do You See? 99% Fail!
/ 98 viewsWhat Do You See? 99% Fail! ▶ Facebook: https://www.facebook.com/WOWQuiz ▶ Twitter: https://twitter.com/WOWQuizVideo 4 Logic Puzzles That Will Leave You Scratching Your Head https://www.youtube.com/watch?v=dbVT2437Ys Only People With An IQ Of 141 Can Solv

05:26
Can you solve the dark coin riddle?  Lisa Winer
/ 368 viewsPractice more problemsolving at https://brilliant.org/TedEd/ Solution to the bonus riddle mentioned at the end: https://brilliant.org/tededcoinflip You heard the travelers’ tales, you followed the maps, and now, you’ve finally located the dungeon contain
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03:36
90% people fail!! (How smart are you?  test with answers)
/ 133 viewsLet me know your answers!  10,000 comments = Happy Broccoli! ★★ For more Brain brocs... Subscribe to DB! ★★ This sequence of animal questions will likely mess you up... It's a type of creative IQ test that will test how smart you are. I didn't answer the

02:13
Crazy Math Trick: I will guess Your Age! (OLD 2016 version)
/ 105 viewsCheck here for the 2017 version: https://www.youtube.com/watch?v=PQjNF34H3Bs&feature=youtu.be ★★ For more broccolies like this... Subscribe to DB! ★★ I will guess your age! This is a crazy math trick that is likely to impress you and your friends too! You

05:19
Riddles: 5 "easy"... & one IMPOSSIBLE! (with answers)
/ 111 views★★★★ Riddles and more... Subscribe to Daily Broccoli! ★★★★ This is a fun video with 5 supposedly "easy" riddles with answers, and one impossible question. I love these riddles, because they are clever and in fact not all that difficult. But still I wasn't

10:07
New IQ Test! (with answers)
/ 107 views★★ More Broccoli = More IQ :DD (Please subscribe!!!) ★★ This IQ test is amazingly accurate. Check how many questions you got right and what it means in terms of your IQ. Are you smart? How intelligent are you? What is my IQ? This new IQ Test will tell you

02:13
Crazy Math Trick: I will guess Your Age! (2017 with answers)
/ 134 views★★ For more broccolies like this... Subscribe to DB! ★★ I will guess your age! This is a crazy math trick that is likely to impress you and your friends too! You start with a RANDOM number and then end up with your Age and that number... pretty incredible

04:26
97% Fail... Test your EYES! (incl. secret message)
/ 127 views★★ Secret message because... we reached + 278k SUBS!!!! ★★ Massive thank you! You are the best!! The überchallenge is to be able to find all the letters that are hidden in the images. ...if you see all 12 letters, you must have massively good eyes! This i

01:52
Three Solutions! Can You Find Them? (math trick with answers)
/ 79 views★★ Please LIKE if you found at least ONE solution!! ★★ This is an impossible equation, because 6+4 is clearly not 4... BUT there are three solutions to this equation by moving just ONE matchstick. Can you find all three solutions? I am curious to see how

04:55
You will NOT know all of these sounds, I am SURE!! (with answers)
/ 88 views★★ For more sound broccolies like this... Subscribe to DB! ★★ You will NOT know all of these sounds, I am SURE!! I would be incredibly surprised if anyone actually identifies all of these animal sounds... This is a listening test to see how well you know

05:14
10 Tricky Questions To Test Your Brain
/ 156 views10 tricky questions to test your brain and IQ level. Subscribe: https://goo.gl/Hnoaw3  Other Videos you might like: 20 Things You Didn't Know About MONEY https://yout

04:13
6 Riddles That Defy Logic
/ 120 views6 Riddles That Defy Logic Facebook: https://www.facebook.com/WOWQuiz Twitter: https://twitter.com/WOWQuizVideo Only Geniuses Can Find All The Differences https://www.youtube.com/watch?v=53II7KUz9ow Only a Genius Can Solve These 7 Brainteasers in 30 Second

05:58
Can You Crack This Four Card Code?
/ 100 viewsA surprisingly tricky card riddle. You'll need to put your thinking caps on for this one. Hi! I'm Jade. I'm an Aussie with a Bachelor's degree in Applied Physics. After three years and over 100 lab sessions, I realized I'm terrible at experiments. So now

12:28
Can You Find the Odd Object Out in These Pictures?
/ 110 viewsCan You Find the Odd Object Out in These Pictures? Facebook: https://www.facebook.com/WOWQuiz Twitter: https://twitter.com/WOWQuizVideo 10 Mind Bending Matchstick Puzzles https://www.youtube.com/watch?v=N1JsKW57sug How Good Are You At Spotting Details? ht

04:48
10 Riddles That Will Trick Your Brain
/ 224 viewsTest your intelligence by answering correctly all these riddles. Subscribe: https://goo.gl/Hnoaw3  Other Videos you might like: 10 CRAZY Mind Game Tricks To Fool Your

05:27
9 Tricky Puzzles That Will Totally Blow Your Brain
/ 150 viewsOnce you show children’s puzzles toadults, most ofthem immediately get abrain freeze. Try to stretch your brain alittle and check ifyou can cope with questions from children’s books! Subscribe to Bright Side : https://goo.gl/rQTJZz 

04:47
Can you solve the egg drop riddle?  Yossi Elran
/ 219 viewsCheck out our Patreon page: https://www.patreon.com/teded View full lesson: https://ed.ted.com/lessons/canyousolvetheeggdropriddleyossielran The city has just opened its oneofakind Faberge Egg Museum, with a single egg displayed on each floor o
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06:34
10 IQ and Riddles For Kids With Tricky Answers
/ 407 views10 IQ and Riddles For Kids With Tricky Answers. These are the best 10 IQ and Riddles For Kids With Tricky Answers. These are perfect for brain teasers for kids, teens and all. Please try this once and do not forget to like, share and comment.

03:54
THESE POPULAR RIDDLES WILL BLOW YOUR MIND  Decipher Riddles & Brain Teasers
/ 249 viewsTHESE POPULAR RIDDLES WILL BLOW YOUR MIND  Decipher Riddles & Brain Teasers These popular riddles on logic can be solved by any kid or adult who has high IQ. These riddles with answers will always test your brain and make your brain scratch. There are th

08:11
7 Riddles That Will Test Your Brain Power
/ 294 viewsThese 7 Puzzles Will Trick Your Brain. Take this fun test tocheck the sharpness and productivity ofyour brain. Try toanswer these 7questions asquickly aspossible and see the results!  Subscribe to our new channel 'SLICK SLIME SAM'  https://goo.gl/zarV

07:19
11 Simple Riddles That Most People Can't Solve
/ 477 views12 tricky riddles you probably haven’t heard of. Try to find the right answers to check whether you’re a true genius! Subscribe to Bright Side : https://goo.gl/rQTJZz 
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05:51
Brain Games: Can you outsmart these puzzles?
/ 116 viewsJason Silva, host of National Geographic's program "Brain Games," speaks to the "CBS This Morning" cohosts about using experiments to challenge what we think we know about the brain.

02:48
Brain Teasers  Brain Games
/ 104 viewsComedian Ben Bailey is quizzing people's common sense with a few trick questions. Think you can't be fooled? Listen carefully and play along to find out how you fare. ➡ Subscribe: http://bit.ly/NatGeoSubscribe About Brain Games: Using a series of experime

02:42
Brain Games Challenge: YOU WILL FAIL!
/ 80 viewsBrain teaser having been featured on National Geographic. If you haven't seen it before this might just be impossible! Challenge your friends on Facebook. See the revised version here: https://www.youtube.com/watch?v=BZWSU_uRo Like, Comment, and Subscri

06:35
Only a Genius Can Solve These Riddles in 2 Minutes
/ 221 viewsLogic puzzles are good for people of all ages because they give our minds a chance to limber up. Can you solve each of them in 15 seconds? If so, you can consider yourself a genius (we aren’t – we couldn’t get the last one). Subscribe to Bright Side : htt

07:42
7 Visual Riddles to Test Your Brain Speed
/ 168 viewsOnly a true genius can solve these 7 visual riddles in less than a minute. Subscribe to Bright Side : https://goo.gl/rQTJZz  Our Social Media: Facebook: https://www.fa

10:44
18 Tricky Riddles That'll Stretch Your Brain
/ 384 viewsSubscribe to Bright Side : https://goo.gl/rQTJZz For copyright matters please contact us at: welcome@brightside.me  We've prepared some fun brain teasers that kids cra
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04:01
Can you find the next number in this sequence?  Alex Gendler
/ 181 viewsView full lesson: http://ed.ted.com/lessons/canyoufindthenextnumberinthissequencealexgendler 1, 11, 21, 1211, 111221. These are the first five elements of a number sequence. Can you figure out what comes next? Alex Gendler reveals the answer and

04:50
Can you solve the fish riddle?  Steve Wyborney
/ 437 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethefishriddlestevewyborney As the cargo director on the maiden voyage of the S.S. Buoyant, you’ve agreed to transport several tanks containing the last specimens of an endangered fish species t
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03:44
The Train Bird Problem: What's Your Approach?
/ 131 viewsThe Rest Of Us on Patreon: https://www.patreon.com/TheRestOfUs The Rest Of Us on Twitter: http://twitter.com/TROUchannel The Rest Of Us TShirts and More: http://teespring.com/TheRestOfUsClothing

00:36
How to create chocolate out of nothing
/ 134 viewsDiscover my other interactive magic here: http://www.marianotomatis.com Wanna solve world hunger with magic? This video will teach you how to create chocolate out of nothing. Here the cyclic GIF: http://www.marianotomatis.it/blog/images/20130409a.gif To u

22:41
Calculating the optimal sphere packing density: with oranges
/ 123 viewsCheck out the corresponding video I made with Steve Mould for his channel. https://youtu.be/O3RsDIWB7s0 Thomas Hales’s proof of the Kepler Conjecture. http://annals.math.princeton.edu/wpcontent/uploads/annalsv162n3p01.pdf The Kepler Conjecture on wiki

05:07
Check your intuition: The birthday problem  David Knuffke
/ 237 viewsView full lesson: http://ed.ted.com/lessons/checkyourintuitionthebirthdayproblemdavidknuffke Imagine a group of people. How big do you think the group would have to be before there’s more than a 50% chance that two people in the group have the same
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05:24
Can you solve the pirate riddle?  Alex Gendler
/ 603 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethepirateriddlealexgendler It’s a good day to be a pirate. Amaro and his four mateys – Bart, Charlotte, Daniel, and Eliza have struck gold – a chest with 100 coins. But now, they must divvy up
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05:13
Can you solve the virus riddle?  Lisa Winer
/ 413 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethevirusriddlelisawiner Your research team has found a prehistoric virus preserved in the permafrost and isolated it for study. After a late night working, you’re just closing up the lab when a

01:52
How to Solve a Rubik's Cube  FullTime Kid  PBS Parents
/ 204 viewsWatch Mya [unofficially] break the world record for solving a Rubik's cube, blindfolded! You won't REALLY learn how to solve the puzzle , but you'll learn a neat trick to show your friends and family. Executive Producer: Danielle Steinberg Meet Mya! She'

01:51
Test your math IQ  Part 1
/ 129 viewsTest your math IQ with this fun question. There are two 12 sided coins. Find the measure of the angle when the coins are side by side. Each side of the coin is equal length. My name is Chris and my passion is to teach math. Learning should never be a stru

01:07
The Easiest Brain Teaser You Might Get Wrong
/ 174 viewsTry and solve the easiest brain teaser you might get wrong. The chicken costs $1.00 more than the egg, and together they cost a total of $1.06. How much does the egg cost? My name is Chris and my passion is to teach math. Learning should never be a strugg

01:27
The Easiest Brain Teaser that will rack your brain
/ 220 viewsThis is the easiest brain teaser that will rack your brain. 5 people can build 5 houses in 5 days. How long will it take 100 people to build 100 houses? My name is Chris and my passion is to teach math. Learning should never be a struggle which is why I m

30:07
Mind Bending Math: Riddles and Paradoxes
/ 154 viewsLearn that determining the will of the voters can require a mathematician. Delve into paradoxical outcomes of elections at national, state, and even club levels. Study Kenneth Arrow’s Nobel prizewinning impossibility theorem, and assess the U.S. Electora

04:54
Can you solve the three gods riddle?  Alex Gendler
/ 340 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethethreegodsriddlealexgendler You and your team have crashlanded on an ancient planet. Can you appease the three alien overlords who rule it and get your team safely home? Created by logician

03:29
Mind blowing brain teaser  Folding paper to the moon
/ 162 viewsCan you solve this mind blowing brain teaser? How many times can you fold a piece a paper before it reaches the moon? Find out the solution in this brain teaser in this video. My name is Chris and my passion is to teach math. Learning should never be a st

04:33
Can you solve Zeno's paradox?  Brain Teaser
/ 166 viewsZeno's paradox is one of the most well know math puzzles in history. Is it possible to add an infinite amount of numbers and get an exact value? This is one example of Zeno's paradox. Try and solve this paradox and learn about the Greek philosopher Zeno i

01:36
Are you smart enough to solve this simple brain teaser?
/ 167 viewsThis simple brain teaser is not so easy. A virus is doubling every singe day. On the 67th day the virus has reached its max population. When will the virus reach half of its max population. My name is Chris and my passion is to teach math. Learning should

03:51
Can You Solve This MIT Admissions Question? Geometry Problem, 1869
/ 175 viewsThe Massachusetts Institute of Technology (MIT) is one of the top ranked universities in the world. This question appeared on its admissions exam nearly 150 years ago. "The perpendicular dropped from the vertex of the right angle upon the hypotenuse divid

08:04
Can you solve the burning stick riddle? ft Simone Giertz part 3/3
/ 154 viewsHow can you time 45 minutes with 2 sticks that each burn for one hour? Simone's channel: https://www.youtube.com/channel/UC3KEoMzNz8eYnwBC34RaKCQ First riddle video: https://www.youtube.com/watch?v=qplG78Guaa4 Second riddle video: https://youtu.be/ri49dTl

06:31
The Boat/Rock Brainteaser ft Simone Giertz part 2/3
/ 140 viewsVideo on Simone's channel! https://www.youtube.com/watch?v=O3G9PuDZ_8c&t=40s Simone's channel: https://www.youtube.com/channel/UC3KEoMzNz8eYnwBC34RaKCQ First riddle video: https://www.youtube.com/watch?v=qplG78Guaa4 0:22  riddle #1  the falling wooden a

04:09
Can you solve these physics riddles? ft Simone Giertz  Part 1/3
/ 154 viewsReading comments on Simone’s channel: https://www.youtube.com/watch?v=O3G9PuDZ_8c Check out Simone’s robots! https://www.youtube.com/simonegiertz Creator: Dianna Cowern Editor: Jabril Ashe Kyle Norby/ Dianna Cowern Thanks to Dan Walsh! Subscribe to Physic

02:41
Trick Question  True or False
/ 258 viewsThink you can answer this simple trick question? Does .9 repeating equal 1? Find the solution in this video. My name is Chris and my passion is to teach math. Learning should never be a struggle which is why I make all my videos as simple and fun as possi
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01:32
Easy Puzzle  But can you solve it?
/ 150 viewsSolve this puzzle by cutting the piece of wood into two pieces. Both pieces must fit exactly into the hole. Can you solve this easy puzzle? Watch the video and find out. My name is Chris and my passion is to teach math. Learning should never be a struggle

04:35
Can you solve the counterfeit coin riddle?  Jennifer Lu
/ 260 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethecounterfeitcoinriddlejenniferlu You’re the realm’s greatest mathematician, but ever since you criticized the Emperor’s tax laws, you’ve been locked in the dungeon. Luckily for you, one of t
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03:16
Can You Solve This 8th Grade Geometry Problem? 75% Got The Wrong Answer
/ 165 viewsWhat is angle A in the starshaped figure? This problem appeared on the 1999 AMC 8 test (intended for 8th grade students in the US). Approximately 75% of testtakers did not mark the correct response. Can you figure it out? Watch the video for a solution.

06:24
Can You Solve The Missing Sock Puzzle?
/ 129 viewsA statistician keeps a simple wardrobe. He only purchases pairs of black socks and white socks, and he keeps all of the socks in a pile in the drawer. Recently one of the socks was lost in the laundry. The socks have a mathematical property. If you select

06:18
Can You Solve The Diluted Wine Puzzle?
/ 151 viewsA servant has a method to steal wine. He removes 3 cups from a barrel of wine and replaces it with 3 cups of water. The next day he wants more wine, so he does the same thing: he removes 3 cups from the same barrel (now with diluted wine) and replaces it

04:38
Can you solve the airplane riddle?  Judd A. Schorr
/ 297 viewsView full lesson: http://ed.ted.com/lessons/canyousolvetheairplaneriddlejuddaschorr Professor Fukanō, the famous scientist, has embarked on a new challenge – piloting around the world in a plane of his own design. There’s just one problem: there's

05:27
Can You Solve The MindBending SelfCounting Sentence Riddle?
/ 239 views"In this sentence, the number of occurrences of the digit 0 is __, of the digit 1 is __, of the digit 2 is __, of the digit 3 is __, of the digit 4 is __, of the digit 5 is __, of the digit 6 is __, of the digit 7 is __, of the digit 8 is __, and of the d

04:13
Can You Solve This Grade 12 Geometry Problem From Australia? The Marshmallow Chocolate Puzzle
/ 173 viewsA marshmallow has the shape of a cylinder with diameter 5 and height 3. A dessert is made with 24 marshmallows: there are two stacked layers of marshmallows, and each layer has 3 rows of 4 marshmallows. The gaps between the marshmallows are filled with ch

07:49
Can You Solve The Viral 9 = 72 Puzzle? The Correct Answer Explained
/ 201 viewsThis problem has been shared millions of times on Twitter/Facebook with the claim "99% fail" to solve it and that only a genius could find the correct answer. If 9 = 72, 8 = 56, 7 = 42, 6 = 30, 5 = 20, then 3 = ? In this video I explain what many people b

04:30
Adults Are Arguing About This 3rd Grade Math Problem
/ 173 views"If Sue runs around the track twice, and John runs around the track four times more than Sue, how many times does John run around the track?" This problem was given to 3rd graders. A parent disagreed with the answer the teacher was marking. After it was p

09:11
Can You Solve The Rectangle Ratio Puzzle? The Surprising Answer
/ 179 viewsStart with a unit square (a rectangle with both sides equal to 1, call it R1). Attach a rectangle of area 1 to its right side, then attach a rectangle of area 1 to its top. The border of this new shape is another rectangle, call it R2. We can repeat the p

02:45
The Day After Tomorrow Is Yesterday Riddle. Can You Solve It?
/ 178 viewsThis puzzle is popular on Facebook and many other sites. "When the day after tomorrow is yesterday, then today will be as far from Wednesday as today was from Wednesday when the day before yesterday was tomorrow. What day is today?" Can you solve this tri

07:47
Can You Solve The Probability The Newborn Is A Boy? Many Fail This Interview Question
/ 197 viewsThis problem has been asked in job interviews. On the morning of January 1, a hospital nursery has 3 boys and some number of girls. That night, a woman gives birth to a child, and the child is placed in the nursery. On January 2, a statistician conducts a

04:19
Can you solve the river crossing riddle?  Lisa Winer
/ 556 viewsView full lesson: http://ed.ted.com/lessons/canyousolvetherivercrossingriddlelisawiner As a wildfire rages through the grasslands, three lions and three wildebeest flee for their lives. To escape the inferno, they must cross over to the left bank
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03:48
Can You Solve This Harvard Admissions Question? Algebra Problem, 1869
/ 207 viewsThe Harvard admissions exam in 1869 included this algebra problem: "A man bought a watch, a chain, and a locket for $216. The watch and locket together cost three times as much as the chain, and the chain and locket together cost half as much as the watch

05:57
Can You Solve This 6th Grade Geometry Problem From Singapore? The Area Of A "Claw"
/ 302 viewsThis problem was given to Primary 6 (age 1112) students in Singapore. What is the area of the shaded region in the video, which consists of the region bounded by 4 quarter circles in a 3x3 grid of squares, and each square has a side length of 4? The shad

07:39
Can You Solve The Alien Extinction Riddle? Hard Job Interview Question
/ 226 viewsA single alien lands on Earth. Every day after that, each alien on Earth undergoes a transformation, which could be any of the four equally likely events: (a) the alien dies, (b) the alien does nothing, (c) the alien replicates itself (2 aliens total), (d

11:27
Can You Solve The Viral 11x11 = 4 Puzzle? The Correct Answer Explained
/ 304 viewsIf 11x11=4 and 22x22=16, what is 33x33=? This puzzle has been shared with the claim that only geniuses can solve it. It has gotten millions of views on the internet and Facebook as people have debated the correct answer. In this video I present what many

04:53
Can you solve the prisoner boxes riddle?  Yossi Elran
/ 319 viewsView full lesson: http://ed.ted.com/lessons/canyousolvetheprisonerboxesriddleyossielran Your favorite band is great at playing music...but not so great at being organized. They keep misplacing their instruments on tour, and it’s driving their mana
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02:06
Can You Solve The Viral Matchstick Puzzle 6 + 4 = 4?
/ 282 viewsCan you fix 6 + 4 = 4 by moving 1 matchstick? This problem has gone viral on Facebook, with one post having over 400,000 shares. The ground rules are you cannot break a stick, it should be an equality (=), and you have to use 7segment numbers (the block

03:04
Trick Question  Find the missing dollar
/ 180 viewsTrick question! Three friends are overcharged for their hotel room. The hotel decides to refund the difference. After the hotel issues the refund one dollar has mysteriously disappeared. Where is the missing dollar? Find the solution to this trick questio

02:21
Trick Question  Test your math skills
/ 166 viewsFind the maximum and minimum values of X in this trick question. Each value of X must satisfy the given inequality. Test your math skills and have fun with this trick question. My name is Chris and my passion is to teach math. Learning should never be a s

02:51
The Horse Horseshoe Boots Viral Algebra Problem  The Correct Answer Explained
/ 396 viewsA lot of people are arguing over the correct answer to this algebra problem involving horses, horseshoes, and boots. A Facebook post with this problem has over 500,000 comments. Can you figure it out? In this video I explain the correct answer. Blog post:

05:33
What is 6÷2(1+2) = ? The Correct Answer Explained
/ 289 viewsWhat is 6÷2(1+2) = ? This problem went viral and generated millions of comments on Facebook, Twitter, YouTube and social media sites. I explain how to get the correct answer by using the modern interpretation of the order of operations. I also explain how
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07:25
Can You Solve The Race To December 31 Riddle?
/ 163 viewsHere's a fun game you can play with another person. The game starts on January 1. Each of two players takes turns calling out another date. The new date has to be a later date in the year with either the same month OR the same day (from January 1, a playe

08:05
Can You Solve The Hardest Easy Geometry Problem?
/ 239 viewsIn the figure, what is the value of angle x? This problem is known as Langley's Adventitious Angles. It is also known as the hardest easy geometry problem because it can be solved by elementary methods but it is notoriously difficult to work out. Can you

05:55
"Impossible" Logic Puzzle  How Many Liars Are At The Party?
/ 209 viewsA party has 100 people who are either liars are truth tellers. Liars always lie and truth tellers always say the truth. After the party you ask each person, "How many truth tellers did you shake hands with?" Each person gives a different answer from 0 to

05:08
Can you solve this pier puzzle?
/ 152 viewsThis math brainteaser challenges you to find a simple, elegant solution to a seemingly complex problem! Can you figure it out? There are two towns near a shore. They want to build a pier on the shoreline with a path connecting the pier to each town. They

06:01 Popular
Can You Solve The Viral 1 + 4 = 5 Puzzle? The Correct Answer Explained
/ 1,549 viewsThis problem was shared on Facebook with the claim that only one in a thousand could figure it out. It went viral and generated over 3 million comments. Here is the problem. If 1 + 4 = 5, 2 + 5 = 12, 3 + 6 = 21, what is 8 + 11 = ? This video presents what

06:24
Can You Solve The Chameleon Riddle?
/ 247 viewsA museum has 13 blue, 15 red, and 17 green chameleons. Whenever two chameleons of different colors meet, they both change into the color of the other chameleon (if blue and red met, for example, they would both turn green). As the chameleons mingle, is it

07:21
Can You Solve The Magical Pond Puzzle?
/ 192 views(Same video with music: https://youtu.be/nFGpk0ZpRk) You visit a shrine that has 3 temples. Before each temple, you have to swim in a magical pond. Your path is pondtemple1pondtemple2pondtemple 3. Each time you swim, the pond magically triples the n

05:26
Can You Solve The Red Ball Lottery Puzzle?
/ 152 views(Same video without the music: https://youtu.be/sz5oLEpc8xE) This problem involves 100 red balls, 100 blue balls, and 2 urns. First you distribute all the balls between the 2 urns, placing at least 1 ball in each urn. Next, you select an urn at random, an

04:08
Can You Solve The Passcode Riddle?  Ganesh Pai
/ 518 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethepasscoderiddleganeshpai In a dystopian world, your resistance group is humanity’s last hope. Unfortunately, you’ve all been captured by the tyrannical rulers and brought to the ancient colis
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01:49
This Matchstick Puzzle Is
/ 181 viewsThis classic matchstick/toothpick puzzle is making the rounds because it is supposedly "extremely hard" for adults. Can you make 3 squares by moving 3 matchsticks? You cannot break any of the sticks, the resulting squares must be of equal size, and each t
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07:10
TOUGH Interview Question  Ways To Give 11 Coins To 3 People
/ 166 viewsHow many ways can you divide 11 coins to 3 people? How many ways are there if each person has to get at least 1 coin? This puzzle is an example of a technical interview question. The video demonstrates the solution, which indicates the number of nonnegat

06:57
When Is Christmas? Mentally Convert Date To Day Of The Week
/ 145 viewsJanuary 1, 2016 is a Friday. When will Christmas be in 2016? What about Christmas in 2055? You can do this in your head! Blog post (text explanation): http://wp.me/p6aMk4qQ Doomsday Rule (previous video): https://www.youtube.com/watch?v=UsStBxY9STw Calcu

04:22
Impossible Algebra Problem
/ 401 viewsThis problem is making the rounds. Can you place numbers in the four boxes so all the equations are true? Blog post (text/image explanation): http://wp.me/p6aMk4up If you like my videos, you can support me at Patreon: http://www.patreon.com/mindyourdecis

03:25
Can You Solve This? AA + BB + CC = ABC
/ 323 viewsIf AA + BB + CC = ABC, what are the values of A, B, and C? All the digits are distinct and positive. Watch the video for a solution. Blog (text explanation): http://wp.me/p6aMk4Cm If you like my videos, you can support me at Patreon: http://www.patreon.c

02:57
Viral Facebook Math Problem
/ 291 viewsThis problem has over 2 million comments on Facebook and is getting coverage in mainstream media and blogs. Can you figure out this Facebook fruit algebra puzzle involving apples, bananas, and coconuts? The video presents what many people consider to be t

06:24
The Seemingly Impossible Escape Logic Puzzle
/ 277 viewsAn evil logician takes Alice and Bob captive. They have a chance to escape if they can deduce the total number of trees in the prison. Can they figure it out? Source of puzzle wu: riddles forum https://www.ocf.berkeley.edu/~wwu/cgibin/yabb/YaBB.cgi?board

01:18
Can You Make 4 Triangles From 6 Matches?
/ 252 viewsCan you use 6 matches to make 4 triangles of equal size and equal shape? This is harder than it sounds! Give it a try before watching the video for a solution. If you like my videos, you can support me at Patreon: http://www.patreon.com/mindyourdecisions

07:52
Find The 10 Digit Number Classic Puzzle And Solution
/ 160 viewsI'm thinking of a 10 digit number that uses the each digit 0 to 9 exactly once and where the number formed by the first n digits is divisible by n. What could my number be? The video explains how to find the answer using tests for divisibility. Blog post:

01:57
I Will Read Your Mind  Math Magic Trick
/ 343 viewsPick a 2 digit number. Got it? Now and add up the digits. Subtract that from your original number. Look up the resulting number in the table. Can I figure out the symbol you are looking at? This video predicts your symbol and explains why this math trick
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03:33
Can You Solve This Intelligence Test? Viral Facebook Puzzle
/ 179 viewsIf 6 + 4 = 210, and 9 + 2 = 711, what is the rule to combine numbers? This "intelligence test" has been shared more than 3 million times on Facebook. On Twitter people claim solving it means you have an IQ of more than 150 (genius level). In this video I

04:52
Can You Solve The Two Rope Puzzle?
/ 169 viewsYou have two ropes and a lighter. Each rope burns in 60 minutes, but the ropes do not burn at a constant rate. How can you measure 45 minutes by burning the ropes? Some of you might have heard this problem before. If so, try this variation: how can you me

08:27
Can You Solve The 3 Cards Riddle?
/ 182 viewsThere are 3 cards in this problem. One card is blue on both sides, another is red on both sides, and the last is red on one side and blue on the other. The cards are put in a bag and I pick one at random. Without looking at the colors on the card, I place

02:57
Can You Solve This Crazy Equation? Ramanujan's Radical Brain Teaser
/ 164 viewsIn 1911, Srinivasa Ramanujan posed this problem involving an infinite nested radical (a neverending expression that has square roots inside of square roots). Can you figure out how to simplify the equation? The video presents an intuitive solution. Techn

03:09
Can You Solve The Marriage Logic Problem? 80% Fail
/ 162 viewsSurveys have found 80 percent get this logic problem wrong. Alice is looking at Bob, and Bob is looking at Charlie. Alice is married; Charlie is not. Is a married person looking at an unmarried person? Answer choices are A) Yes, B) No, and C) Cannot be de

05:09
Can You Solve The Snake Eyes Probability Riddle?
/ 180 viewsYou close your eyes and roll a pair of dice. The casino dealer announces that at least one of the rolls is showing a 1.What is the probability that both dice are showing a 1? Watch the video for the solution. (Snake eyes is a term for rolling a pair of 1s

02:37
Adults Stumped By Maths Questions For 15 Year Olds. Can You Solve Them?
/ 215 viewsHow hard are math tests? A survey asked 2,000 UK adults to answer sample GCSE test questions intended for 15 year old students. On average, the survey questions were missed by about 40% of adults. Can you solve them? The video presents 2 questions that ma

04:13
Adults Stumped By Geometry Problems For 10 Year Olds. Can You Solve Them?
/ 183 viewsThese homework problems were given to 10 year old children (Year 5) in England (Glossop, Derbyshire) and they were posted to Facebook when some adults found them to be difficult. One person claimed the problems were impossible to solve. Can you figure the

03:28
Flower Math Problem  Adults Stumped By Question For Kids In China
/ 240 viewsThis problem is said to come from a test given to a Chinese kindergarten class (5 year olds). It was posted online and caused a lot of debate as adults were stumped about the correct answer, some saying it is impossible. Can you figure it out? This video

04:01
Can You Solve The Control Room Riddle?  Dennis Shasha
/ 395 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethecontrolroomriddledennisshasha As your country's top spy, you must infiltrate the headquarters of the evil syndicate, find the secret control panel, and deactivate their death ray. But your
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05:05
Try This April Fools' Trick! (Mystery Math)
/ 298 viewsHere's a simple trick you can play on your friends!
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03:50
Can You Solve The Locker Riddle?  Lisa Winer
/ 554 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethelockerriddlelisawiner Your rich, eccentric uncle just passed away, and you and your 99 nasty relatives have been invited to the reading of his will. He wanted to leave all of his money to yo
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02:24
Will A Cat Win A Race Against A Dog?
/ 264 viewsYou may have heard about the race between the tortoise and the hare, but have you heard about the race between the cat and the dog? SUBSCRIBE NOW http://www.youtube.com/subscription_center?add_user=CuriosityShow CONNECT WITH CURIOSITY Facebook ➤ http://ww

03:56
Mind Reading With Numbers
/ 261 viewsWhen someone is thinking of any number between 1 and 1000, Deane shows how to find that number with just 10 questions. It may seem like mind reading, but it is really logic. SUBSCRIBE NOW http://www.youtube.com/subscription_center?add_user=CuriosityShow C
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01:32
Restaurant Puzzle Strange Code
/ 141 viewsDeane and Rob decipher a coded message left in a restaurant. SUBSCRIBE NOW http://www.youtube.com/subscription_center?add_user=CuriosityShow CONNECT WITH CURIOSITY Facebook ➤ http://www.facebook.com/CuriosityShow Twitter ➤ https://twitter.com/CuriositySho

04:31
Can You Solve The Frog Riddle?  Derek Abbott
/ 483 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethefrogriddlederekabbott You’re stranded in a rainforest, and you’ve eaten a poisonous mushroom. To save your life, you need an antidote excreted by a certain species of frog. Unfortunately, on
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04:13
Can You Solve The Temple Riddle?  Dennis E. Shasha
/ 381 viewsView full lesson: http://ed.ted.com/lessons/canyousolvethetempleriddledenniseshasha Your expedition finally stands at the heart of the ancient temple. But as you study the inscriptions in the darkness, two wisps of green smoke burst forth. The wal

03:10
Don't Checkmate  Brain Teaser
/ 189 viewsDon't checkmate the black king. In this brain teaser you must find one move for white which will not result in immediate checkmate for the black king. I also have a bunch of other fun brain teasers as well. My name is Chris and my passion is to teach math

02:04
Guess The Diagonal  Brain Teaser
/ 184 viewsTry to solve this brain teaser in less than a minute. You must guess the diagonal inside of the circle. There is enough information given which allows you to find the length of the diagonal in less than a minute. My name is Chris and my passion is to teac

04:09
Counterfeit Coins  Brain Teaser
/ 160 viewsFind the counterfeit coins in one of the eight bags! You may only use the weight scale once in this brain teaser. How do you know which bag has the counterfeit coins? I also have a bunch of other fun brain teasers as well. Heaven and hell  Brain Teaser h

01:51
Crossing The River  Brain Teaser
/ 249 viewsTry to solve this fun brain teaser. Cross the river with all of the zombies and humans. The boat can only fit two at a time. Also there can never be more zombies than humans. My name is Chris and my passion is to teach math. Learning should never be a str

06:35
Bisecting Yin And Yang  Brain Teaser
/ 208 viewsCan you bisect yin and yang using a straight line? Find the solution to this brain teaser in this video. I also have a bunch of other fun brain teasers as well. Heaven and hell  Brain Teaser https://www.youtube.com/watch?v=YOgKI0HWCnA Two burning ropes 

03:40
Two Burning Ropes  Brain Teaser
/ 191 viewsTwo burning ropes are needed to measure 45 minutes exactly. Each rope takes exactly one hour to burn, but they don't burn at a constant rate. Each rope is made of a different material and burns differently from the other. How do we measure 45 minutes exac

05:13
Can You Solve
/ 274 viewsView full lesson: http://ed.ted.com/lessons/canyousolveeinsteinsriddledanvandervieren View all the clues here: http://ed.ted.com/lessons/canyousolveeinsteinsriddledanvandervieren#digdeeper Before he turned physics upside down, a young Al

03:19
Heaven And Hell  Brain Teaser
/ 286 viewsFun brain teaser in which you have to choose between two doors. One of the doors leads to heaven and the other door leads to hell. You are allowed to ask the guards one question. What is one question that would guarantee certainty of choosing the door to

08:29
The Uncracked Problem With 33  Numberphile
/ 188 views33 is the lowest unsolved problem in the world of "summing three cubes". But 30 was also a tough nut to crack! Featuring Tim Browning from the University of Bristol. Taxi Cab Numbers: https://youtu.be/LzjaDKVC4iY Fermat's Last Theorem: https://youtu.be/qi

04:52
Can You Solve The Boat Puzzle?
/ 308 viewsYou throw a rock in water from your boat. Can you figure out what happens to the water level? physicsgirl.org instagram.com/thephysicsgirl facebook.com/thephysicsgirl twitter.com/thephysicsgirl Host/Writer/Editor: Dianna Cowern With help from: Jimmy Wong
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04:35
Can You Solve The Prisoner Hat Riddle?  Alex Gendler
/ 479 viewsView full lesson: http://ed.ted.com/lessons/canyousolvetheprisonerhatriddlealexgendler You and nine other individuals have been captured by superintelligent alien overlords. The aliens think humans look quite tasty, but their civilization forbids

03:35
Answering Question From Visual Inequality System
/ 143 viewsAnswering question from visual inequality system

03:50
Can You Solve The Bridge Riddle?  Alex Gendler
/ 594 viewsView full lesson: https://ed.ted.com/lessons/canyousolvethebridgeriddlealexgendler Taking that internship in a remote mountain lab might not have been the best idea. Pulling that lever with the skull symbol just to see what it did probably wasn’t s
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02:07
What Colour Is This Dress? (SOLVED With SCIENCE)
/ 205 viewsShare this video for the sake of the human race!! Get the AsapSCIENCE Book: http://asapscience.com/book Subscribe! bit.ly/asapsci Written by Mitchell Moffit and Greg Brown Instagram and Twitter: @whalewatchmeplz and @mitchellmoffit Clickable: http://bit.l

07:14
How To Win A Guessing Game  Numberphile
/ 354 viewsA clever use of random numbers to improve your odds in a number guessing game. Alex Bellos Books: http://bit.ly/BellosBooks Monty Hall problem: http://bit.ly/MontyHallProb NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook: http://ww
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04:42
The Famously Difficult Greeneyed Logic Puzzle  Alex Gendler
/ 511 viewsView full lesson: http://ed.ted.com/lessons/thefamouslydifficultgreeneyedlogicpuzzlealexgendler One hundred greeneyed logicians have been imprisoned on an island by a mad dictator. Their only hope for freedom lies in the answer to one famously di

05:48
Winning At Rock Paper Scissors  Numberphile
/ 307 viewsSquarespace: http://www.squarespace.com/numberphile This video features Hannah Fry  https://twitter.com/fryrsquared More on this topic (and lizards): http://youtu.be/Z8lv2vy5vco And even more on this topic: http://youtu.be/ygHwBxWyI6E The paper: http://b
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03:15
Should You Catch A Tossed Coin?  Numberphile
/ 253 viewsRandomness expert (and former magician) Persi Diaconis on whether it is best to catch a coin or let it fall to the ground. Main video: http://youtu.be/AYnJv68T3MM Extra footage: http://youtu.be/9RKKoXw7wJw Superbowl coin tosses: http://youtu.be/bFfSfzjhfC
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11:34
That Viral Math Problem (Cheryl's Birthday)  Numberphile
/ 251 viewsSimon Pampena gives his take on THAT viral math problem from Singapore. EXTRA FOOTAGE for this video: http://youtu.be/MjYngjjpJg Simon on Twitter: https://twitter.com/mathemaniac NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook: h

12:56
Monkeys And Coconuts  Numberphile
/ 253 viewsAn old problem which baffled many people. Featuring Dr Tony Padilla. Editing and animation in this film by Pete McPartlan  https://twitter.com/petemcpartlan NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook: http://www.facebook.com

01:38
An Impossible Bet
/ 323 viewsShould you take the bet? Click here to find out: http://youtu.be/C5I0bAuEUE Thanks to my friend Dan Hoff for introducing me to this problem! MinutePhysics is on Google+  http://bit.ly/qzEwc6 And facebook  http://facebook.com/minutephysics And twitter 
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03:59
Solution To The Impossible Bet
/ 295 viewsThis problem is called the "100 Prisoners Problem", more info on the math here: http://en.m.wikipedia.org/wiki/100_prisoners_problem Thanks to http://www.ifixit.com for supporting us on Subbable! and to Subbable supporter @vicnice137 And thanks to my frie

12:16
3D Path Counting Brain Teaser
/ 209 viewsExtending the path counting to three dimensions More free lessons at: http://www.khanacademy.org/video?v=wRxzDOloS3o

10:42
Path Counting Brain Teaser
/ 221 viewsCounting paths in a square More free lessons at: http://www.khanacademy.org/video?v=9QduzzW10uA

11:19
Light Bulb Switching Brain Teaser
/ 247 viewsTurning light bulbs on and off. More free lessons at: http://www.khanacademy.org/video?v=WNhxkpmVQYw

12:09
Forehead Numbers Brain Teaser
/ 237 viewsThe perfect logicians are at it again. More free lessons at: http://www.khanacademy.org/video?v=jqpQPxWj8gE

11:01
Blue Forehead Room Solution
/ 264 viewsDo not watch before Blue Forehead Room. THIS IS THE SOLUTION! More free lessons at: http://www.khanacademy.org/video?v=xYkTJFbuM0

07:25
Brain Teaser: Blue Forehead Room
/ 253 viewsWhat happens when 100 perfect logicians have to figure out if they each have a blue forehead? More free lessons at: http://www.khanacademy.org/video?v=rBaCDC52NOY

16:59
Alien Abduction Brain Teaser
/ 265 viewsSaving Earth from becoming a mushroom farm. More free lessons at: http://www.khanacademy.org/video?v=K4pocYXOmTQ

11:13
Toggler Brain Teaser
/ 265 viewsSeparating the truthteller from the togglers! More free lessons at: http://www.khanacademy.org/video?v=l3OkPYhDi9w

06:50
Liar Truthteller Brain Teaser
/ 222 viewsHow to get correct advice when you can only ask one question from either a liar or a truthteller (when you don't know who is what) More free lessons at: http://www.khanacademy.org/video?v=69rDtSpshAw