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Binomial Probability question...will choose BEST answer!!?
A new drug has been found to be effective in treating 59% of the people afflicted by a certain disease. If the drug is administered to 505 people who have the disease, what are the mean and the standard deviation of the number of people for whom the drug can be expected to be effective?
2 Answers
- PathomaniacLv 41 decade agoFavorite Answer
E(x) = np = (.59)(505) = 297.95
variance = np(1-p) = (505)(.59)(1 - .59) = 122.1595
std deviation = sqrt(variance) = sqrt(122.1595) = 11.0525
- MichaelLv 51 decade ago
The mean would be p * n, or .59 * 505 people.
Mean: 297.95 people
Standard deviation is sqrt (n * p (1-p)) I believe
Std. Dev: 11.05 people
I'm fairly certain about the mean, not so sure about std. dev.
