Pi takes 33 digits to get all 10 digits.
3.14159265358979323846264338327950
However, e only takes 21 digits.
2.71828182845904523536
Suppose you pick random digits from 0 to 9 with probability 1/10 of each digit. What is the average number of digits required to get all 10 digits?

(In reply to Leading answer (spoiler) by Steve Herman)

It is OK to start with 0. Therefore, the first answer is correct.

Posted by Math Man on 2012-07-08 23:08:00