Solution
7.7.1.1
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This is a Binomial distribution with n=25 and p = 0.22.
P(X is at most 5) = F(5) = f(0)+f(1)+f(2)+f(3)+f(4)+f(5) = 0.51843
P(X is at least 5) = 1 - F(4) = 0.67183
\(\displaystyle \mu = np = 25 \cdot .22 = 5.5\)
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