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Question
A fair coin is tossed five times. Find the probability that it shows exactly three times head.
Solution
Let X be the radom variable.
let 'p' be the success and 'q' be the failure
p=1/2, q=1/2
p(Coin shows 3 heads)
=p(x=3)=5c3p3q2
= 10 (1/2)3(1/2)2
=10/32
=5/16
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