A market research firm conducts telephone surveys with a 40% historical response rate.

(3) What is the sampling distribution, mean, and standard deviation of pp, the proportion of individuals who respond to these surveys in a sample of 400 telephone numbers?

Hint: Refer to Section 7.6 in your textbook.

(3) Calculate the probability that in a new sample of 400 telephone numbers, at least 150 individuals will cooperate and respond to the questions?

Hint: What is the probability that the sample proportion will be at least 150/400 = 0.375?