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प्रश्न
The expected value of the number of heads obtained when three fair coins are tossed simultaneously is
(A) 1
(B) 1.5
(C) 0
(D) -1
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उत्तर
(B) 1.5
p=1/2
q=1/2 [∵q=1-(p)]
n=3
Expected value E(X) = np =`3xx1/2=1.5`
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