Two dice are thrown simultaneously. If X denotes the number of sixes, find the variance of X.
Asked by Topperlearning User  4th Jun, 2014, 01:23: PM
Expert Answer:
Let S be the sample space, then n(S) = 36
Favorable cases = n{(1, 6), (2, 6), (3, 6), (4, 6), (5, 6), (6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)}
_{}
X

0

1

2

P(X)

25/36

10/36

1/36

_{}
Thus, variance of random variable X is_{}.
Answered by  4th Jun, 2014, 03:23: PM
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