mgmat probability . please explain?

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mgmat probability . please explain?

by mirantdon » Thu Jul 07, 2011 7:35 am
Jim and Renee will play one game of Rock, Paper, Scissors. In this game, each will select and show a hand sign for one of the three items. Rock beats Scissors, Scissors beat Paper, and Paper beats Rock. Assuming that both Jim and Renee have an equal chance of choosing any one of the hand signs, what is the probability that Jim will win?

5/6
2/3
1/2
5/12
1/3

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by winniethepooh » Thu Jul 07, 2011 8:09 am
1/3
Three possibilities:
Jim wins , Renee wins, stale mate/draw.

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by Frankenstein » Thu Jul 07, 2011 8:12 am
Hi,
If Jim shows one of the three signs, depending on the outcome of Renee, he can either win, draw, or lose with equal probability.
so, probability is 1/3

(or)
Jim wins in the following threes cases:
1)Jim - rock(1/3), Reese - scissors(1/3) -> 1/3*1/3 = 1/9
2)Jim - scissors(1/3), Reese - paper(1/3) -> 1/3*1/3 = 1/9
3)Jim - paper(1/3), Reese - rock(1/3) -> 1/3*1/3 = 1/9

So, probability is 1/9 + 1/9 + 1/9 = 1/3

Hence, E
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by amit2k9 » Thu Jul 07, 2011 11:47 pm
R/S = 1/3*1/3 = S/p = P/r
winning probability = 1/9 * 3 = 1/3.

liked the solution win,lose or draw. Good one.
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