The probability that a person recovers from a disease is 0.8. What is the probability that <strong>EXACTLY</strong> 2 persons out of 5 will recover from the disease?

Explanation

Using the binomial probability formula P(X=r) = {}^nC_r p^r q^{n-r}, where n=5, r=2, p=0.8, and q=0.2. P(X=2) = {}^5C_2 (0.8)^2 (0.2)^3 = 10 \times 0.64 \times 0.008 = 10 \times 0.00512 = 0.0512.

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