Who has the same birthday as me?
Level
pending
There are 400 engineering students sitting in a lecture hall. What is the probability that at least two of these students will share the same birthday?
(Give the answer as number from 0-1. For example 50% is 0.5, 33% is 0.33 and 0% is just 0.)
The answer is 1.
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1 solution
There are 365 (366 if you count leap years!) distinct days to have a birthday in a year, and more than 365 students in the lecture hall. There must be some overlap, thus, there is an 100% (1) that at least two people will share the same birthday.