Question 853653
At a large college, the probability that students are from Ohio is 4%. 
A random sample of 20 students from the college is selected. 
Let X denote the number of students from Ohio among them.
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Using the Normal Approximation to the Binomial Distribution... 
The mean of X is: np = 20*0.04 = 0.8
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The standard deviation of X is: sqrt(npq) = sqrt(0.8*0.96) = 0.8764
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The probability that X is at least 1 is:
P(X at least 1) = 1 - P(X = 0) = 1-(0.96)^20 = 0.558
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Cheers,
Stan H.
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