The SAT Question Everyone Got Wrong

How an SAT question became a mathematical paradox. Head to https://brilliant.org/veritasium to start your free 30-day trial, and the first 200 people get 20% off an annual premium subscription.

I invented Snatoms, a molecule modeling kit where the atoms snap together magnetically. Try it at https://ve42.co/SnatomsV

Huge thanks to Dr. Doug Jungreis for taking the time to speak with us about this SAT question.
Thanks to Stellarium, a wonderful free astronomy simulator https://ve42.co/Stellarium
Thanks to Newspapers.com, a database of historical newspapers https://ve42.co/Newspapers


References:
Summary of this problem by MindYourDecisions https://www.youtube.com/watch?v=kN3AOMrnEUs
More cool math about this problem by Kyle Hill https://www.youtube.com/watch?v=_zCDbB9wvrc
Discussion of a solar day by MinutePhysics https://www.youtube.com/watch?v=nZMMuv0Ltyo
Murtagh, J. (2023). The SAT Problem That Everybody Got Wrong. Scientific American https://ve42.co/SATSciAm
United Press International (1982). Error Found in S.A.T. Question. New York Times https://ve42.co/SAT-NYT
Yang (2020). What's the hardest SAT math problem that you've seen? Quora https://ve42.co/SATQuora
Coin rotation paradox via Wikipedia https://ve42.co/CoinParadox
Simmons, B. (2015). Circle revolutions rolling around another circle. MathStackExchange. https://ve42.co/CircleRoll
Sidereal time via Wikipedia https://ve42.co/SiderealWiki
Solar Time vs. Sidereal Time via Las Cumbres Observatory https://ve42.co/SiderealLCO

Images & Video:
Zotti, G., et al. (2021). The Simulated Sky: Stellarium for Cultural Astronomy Research - https://ve42.co/Stellarium
Newspapers from 1980s - 1990s via Newspapers.com https://ve42.co/Newspapers
SAT Practice Test via the College Board https://ve42.co/PracticeSAT
Revolution Definition via NASA https://ve42.co/RevolutionNASA
Revolution Definition via Merriam-Webster https://ve42.co/RevolutionWebster
Earth motion animation via NASA https://ve42.co/OrbitNASA
Satellite animation via NASA https://ve42.co/SatNASA


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