Probability

2009-03-24 6:19 am

Suppose you roll a six-sided die 10 times. What is the probability of getting three fives in those 10 rolls?

回答 (3)

2009-03-24 6:49 am

✔ 最佳答案

P(E) = 10C3 * (1/6)^3 * (5/6)^7
= 120 * 1/216 * 78125/279936
= 5/9 * 78125/279936
= 390625/2519424
= 0.15504535......

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2009-03-25 3:32 am

3/6*10
=3/60
=1/20

Therfore the ans. is 1/20

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2009-03-24 8:38 am

2*10C3*(1/6)^3*(5/6)^7

2009-03-24 00:46:22 補充：
=18750000/60466176
=390625/1259712
=0.310090719

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