You face an urn with 5555 cards in it, each has a nonzero integer written on it. Nothing is said about the distribution of those numbers. You are told to draw randomly a card, copy the number, return it back, shuffle and draw randomly a card, then write down the sum of both numbers, say S.
(i) Prove: The probability of S being an even number is higher than S being odd.
(ii) Is it true for any initial number of cards? Comment.
(In reply to
Higher numbers before overflow by Charlie)
Based on Charlie's numerical evidence I conjecture that the probability is (N+1)/2N.

Posted by xdog
on 20170214 16:24:49 