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CBSE Class 12-science Answered

Two dice are thrown simultaneously. If X denotes the number of sixes, find the variance of X.
Asked by Topperlearning User | 04 Jun, 2014, 13:23: PM
answered-by-expert 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 | 04 Jun, 2014, 15:23: PM

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