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Question
Given that X ~ B(n= 10, p). If E(X) = 8 then the value of
p is ...........
(a) 0.6
(b) 0.7
(c) 0.8
(d) 0.4
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Solution
(c)
Since X ~ B(n = 10, p),
E(x) = np
10p = 8
p = 0.8
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