Question

1. The Richardson marketing research firm asks you, the analyst, to examine whether the sample of 100 satisfaction ratings provide evidence to support the claim that the population mean u exceeds 50.

(a) How is the sample distributed? Why?

(b) Assume the population mean u=50, x is all the possible sample means, calculate the mean u(x) for all the possible sample means.

(c) Assume the population standard deviation sigma=3.35, x is all the possible sample means, calculate the standard deviation sigma(x) for all the possible sample means.

(d) Based on 1b and 1c above, what is the probability of observing a sample mean above 50.99?

(e) If u=50, what is the percentage for all the possible sample means to be above 50.99? What is your conclusion about this percentage?

Sample means x
u=		n=	sigma=
sigma(x)=sigma/sqrt(n)
P(X>)		norm.dist

Answer 1