# Question

In a particular year, the percentage rates of return of U.S. common stock mutual funds had a normal distribution with a mean of 14.8 and a standard deviation of 6.3. A random sample of nine of these mutual funds was taken.

a. What is the probability that the sample mean percentage rate of return is more than 19.0?

b. What is the probability that the sample mean percentage rate of return is between 10.6 and 19.0?

c. The probability is 0.25 that the sample mean percentage return is less than what number?

d. The probability is 0.10 that the sample standard deviation of percentage return is more than what number?

e. If a sample of 20 of these funds was taken, state whether the probability of a sample mean percentage rate of return of more than 19.0 would be smaller than, larger than, or the same as the correct answer to part (a). Sketch a graph to illustrate your reasoning.

a. What is the probability that the sample mean percentage rate of return is more than 19.0?

b. What is the probability that the sample mean percentage rate of return is between 10.6 and 19.0?

c. The probability is 0.25 that the sample mean percentage return is less than what number?

d. The probability is 0.10 that the sample standard deviation of percentage return is more than what number?

e. If a sample of 20 of these funds was taken, state whether the probability of a sample mean percentage rate of return of more than 19.0 would be smaller than, larger than, or the same as the correct answer to part (a). Sketch a graph to illustrate your reasoning.

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