Probability

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Probability
Message posted by Tim on November 25, 2000 at 12:00 AM (ET)

"In their last 100 chess games played against eachother, Bill has won 46 and Monica has won 54. Using this information and a 95% confidence level, what is the probability that Bill will win a 'best out of seven' series with Monica? The first one to win 4 games is the winner and no more games are played."

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Re: Probability
Message posted by nancy diehl on November 30, 2000 at 12:00 AM (ET)

This problem is a binomial probablity problem. Look the formula up because it's difficult to type it out.
Basically, p=proportion of success would be defined as 46/100=.46.
You also need to compute the number of combinations out of 7 games to have
4 wins. So the other component to the formula is the combination formula of
"7 choose 4". You are looking for the probability x=4.

In English I would do: The combination of 7 choose 4, times .46 to the 4th power, times
.54 to the 3rd power. = .24676 = 24.7% chance

Hence, you need to look this formula up to see how it's applied.

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