Risk Plan50 / 60
MediumProbability

Birthday Problem

Goldman SachsCitadel

What is the smallest number of people in a room for which the probability that at least two share a birthday exceeds 50%? (Ignore leap years.)

Hints

Compute the probability everyone is distinct, then take the complement.

Sign in to reveal the full worked solution, check your answer instantly, and track your progress with spaced-repetition review.