Re: easy dice problem, please quickly help me.
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A fair die is rolled 200 times. What is the probability that a five or a six shows up less than 25% of the time?
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Using Excel =BINOMDIST(49,200,1/3,TRUE) = 0.42%.
This gives the exact answer.
Or using the normal approxmimation:
sigma = sqrt[200*(1/3)*(2/3)] = 6.67.
49 is 2.64 sigma below the average of 66.67, corresponding to 0.41%.
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