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Question
A coin is tossed 5 times. If X is the number of heads observed, find the probability distribution of X.
Solution
Let X = number of heads in 5 tosses. Then the binomial distribution for X has n =5,
\[ = \frac{^{5}{}{C}_r}{2^5}\]
\[\text{ Substituting r = 0, 1, 2, 3, 4, 5 we get the following probability disrtribution } . \]
X 0 1 2 3 4 5
\[P(X) \frac{1}{32} \frac{5}{32} \frac{10}{32} \frac{10}{32} \frac{5}{32} \frac{1}{32}\]
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