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Can You Solve The Probability The Newborn Is A Boy? Many Fail This Interview Question

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Channel: MindYourDecisions
Categories: Brain Teasers   |   Math  
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This 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 survey and selects a child at random from the nursery (including the newborn and every child from January 1). The child is a boy. What is the probability the child born on January 1 was a boy? There are a couple of neat counter-intuitive parts of this problem. Can you figure it out? Watch the video for a solution.

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