Consider a deck of 10 cards numbered in order from 1 to 10. Pick up the first five cards (1 to 5). Randomly discard one and take the 6. Randomly discard one again and take the 7. Continue until the 10 has just been taken.

a) What is the expected average of the five cards in the final hand?
b) What is the expected value of the smallest card in the final hand?

Recompute parts a) and b) where you still hold 5 cards, but go all the way through a 100 card deck.

(In reply to re: computer-assisted solution by Charlie)

Are you sure Charlie. At first glance I calculated the denominator's 19th digit to be an 8 and not a 7. I could be wrong though - I was working it out mentally - while watching the football . . .

Posted by Vernon Lewis on 2007-07-24 04:14:15