Question

A telephone survey of American families is conducted to determine the number of children in the average American family, Past experience has shown that 30% of the families who are telephoned will refuse to respond to the survey. Which of the following statements is not a binomial random variable? A. The number of families out of 50 who refuse to respond to the survey. B. All of the choices are binomial random variables. C. The number of children in a family which responds to the survey. D. The number of families out of 50 who respond to the survey. QUESTION 2 The expected number of heads in 200 tosses of an unbiased coin is A. 75 B. 125 C. 100 D.50 QUESTION 3 4 р In an effort to persuade customers to reduce their electricity consumption, special discounts have been offered for low consumption customers. In Florida, the EPA estimates that 70% of the residences have qualified for these If, instead, a sample of 20 residences is selected, what is the probability 12 or more will have qualified for the discounts discounts?

Answer 1

Question 1)

Answer C) The number of children in the family that responds to the surevy

As the survey is being done with respect to the families, so families as a whole responding or not is a binomial random variable, but not specifically the respond of the children in the families.

Question 2)

Solution:

Expected number of heads = Probability of head * 200

= (1/2) *200

= 100 Answer

Answer : C)100