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A new drug on the market is known to cure 24% of patients with colon cancer. if a group of 15 patients is randomly selected, what is the probability of observing, at most, two patients who will be cured of colon cancer?

User Antlas
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1 Answer

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The final answer is approximately
\(0.0524\).




\[ P(X = 0) = \binom{15}{0} \cdot 0.24^0 \cdot (1 - 0.24)^(15) \]\\


\[ P(X = 0) = 1 \cdot 1 \cdot (0.76)^(15) \]\[ P(X = 0) \approx 0.0021 \]\[ P(X = 1) = \binom{15}{1} \cdot 0.24^1 \cdot (1 - 0.24)^(14) \]\[ P(X = 1) = 15 \cdot 0.24 \cdot (0.76)^(14) \]\[ P(X = 1) \approx 0.0132 \]\[ P(X = 2) = \binom{15}{2} \cdot 0.24^2 \cdot (1 - 0.24)^(13) \]\[ P(X = 2) = 105 \cdot 0.24^2 \cdot (0.76)^(13) \]\[ P(X = 2) \approx 0.0371 \]

Now, add these probabilities:


\[ P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2) \]\[ P(X \leq 2) \approx 0.0021 + 0.0132 + 0.0371 \]\[ P(X \leq 2) \approx 0.0524 \]

User Joinsaad
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