# A probability question, fill in the blank:

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If many letters are written and the corresponding envelopes addressed, and the letters are then fitted at random into the envelopes, the probability that every letter will go into a wrong envelope is extremely close to ____?

Hint: Euler's Constant.

posted Oct 24, 2016

+1 vote
Yes!  You are correct 1/e. Or approximately a 36.8% of a mismatch.

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