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# Probability of flipping and winning

Started by BMAD, Jun 01 2013 03:55 AM

1 reply to this topic

### #1

Posted 01 June 2013 - 03:55 AM

Fearless Frank decided to play a fair coin-flip game with probability 1/2 of winning each

bet, and risked 1/m of his fortune (originally A dollars, m>1) at every flip. After 2n games,

Frank has won n games and lost n. Choose and explain the correct answer from this list:

a) Frank has broken even; he still has his A dollars

b) Frank is predictably ahead by a certain amount

c) Frank is predictably behind by a certain amount (in case b or c give the exact formula in terms of m and n)

d) Frank is now ahead, behind, or even, depending on the order in which the wins and losses occurred

e) He is ahead, behind, or even, depending on m and n

**Edited by BMAD, 01 June 2013 - 03:56 AM.**

### #2

Posted 01 June 2013 - 09:21 PM Best Answer

Spoiler for

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