Hard
Near Impossible Riddles
18 XP

The Binary Birthday

8,251 solved 53% solve rate 47% fail rate
What is the probability that in a room of 70 people, at least two share a birthday?
Only 53% solve this correctly
8,251 attempts
Earn +18 XP for solving
Quick Answer & Explanation
99.9% - far higher

The answer to this riddle is 99.9% - far higher. Difficulty: Hard · Solved by 8,251 puzzle lovers.

99.9% - far higher than most people guess. With just 23 people it exceeds 50%.
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