You play a coin flipping game with 5 coins. On round 1 you flip all of them. On round 2, you pick up all the ones that came up tails (leaving all the heads alone) and flip them again. You continue to do this until all the coins are heads. For example:
Round 1: H T T H T
Round 2: - H T - H
Round 3: - - T - -
Round 4: - - T - -
Round 5: - - H - -
Done in 5 Rounds.
What is the expected number of rounds you'll need to finish the game?
What is the probability you will finish the game in 3 rounds or less?
(In reply to solution (raw form)
Carried to 65 terms, the total comes out 3.794162826420891, where the 65th term was about 2.1x10^-17.
Posted by Charlie
on 2004-10-13 19:46:51