16. Jake an eighth grader from Dayton, Florida took a standardized test. The standardized test was distributed normally with mean 605 and standard deviation 97. Jake scored 432. Lily-also an eighth grader – from Moore, SC took a different standardized test. This test was also normally distributed with a mean of 25 and a standard deviation of 5.3. Lily scored a 37. a) What is the z-score for Jake?
b.) What is the z-score for Lily?
c.) Who scored better? Why?
17. A poll of 20 voters is taken in a very large city. Suppose that the voters were chosen randomly and that their responses were confidential. The purpose is to determine X, the number in favor of a certain candidate for mayor. Suppose that 60% of all the city’s voters favor this candidate. (Suppose that the voters were chosen randomly and that their answer were confidential.) a)What is the distribution of X?
b) List the four criteria for X to have a binomial distribution and discuss whether or not it has a Binomial Distribution.
c) What is the mean of X?
d)What is the standard deviation of X?
e) What is the sample space?

f) Find the probability that X=10. binompdf (n, p, x)
g) Find the probability that X less than or equal to 10.
h) What is the probability that X is less than or equal to 5?
i) What is the probability that X is 5?
j) What is the probability that X is less than 10?

18. Would most wives marry the same man again if given a chance? According to a poll of 608 married women conducted by Ladies Home Journal(June 1988), 80% would, in fact, marry their current husbands. Assume the women in the sample were randomly selected from among all married women in the United States. Does the number X in the sample who would marry their husbands again possess a binomial probability distribution? Explain.

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- Spring '08
- Kyung
- Statistics, Normal Distribution, Probability, Standard Deviation