- #1

CAF123

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## Homework Statement

A and B alternate rolling a pair of dice, stopping either when A rolls the sum 9 or when B rolls the sum 6. Assuming that A rolls first, find the probability that the final roll is made by A.

## The Attempt at a Solution

A rolls a sum 9 on each roll with prob 1/9

B rolls a sum 6 on each roll with prob 5/36

Given that A wins, he will win on an odd number of turns. (since A starts)

Let E be the event that the game finishes on an odd number of turns

Then P(E) = (1/9)(1-5/36)(1/9)(1-5/36)....

Where do I go from here?