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Question : A consumer protection agency is comparing the work of two electrical contractors. The : 2150579

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

13) A consumer protection agency is comparing the work of two electrical contractors. The agency plans to inspect residences in which each of these contractors has done the wiring in order to estimate the difference in the proportions of residences that are electrically deficient. Suppose the proportions of residences with deficient work are expected to be about .3 for both contractors. How many homes should be sampled in order to estimate the difference in proportions using a 90% confidence interval of width .7?

A) n_{1} = n_{2} = 14

B) n_{1} = n_{2} = 19

C) n_{1} = n_{2} = 10

D) n_{1} = n_{2} = 5

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.

15) Two surgical procedures are widely used to treat a certain type of cancer. To compare the success rates of the two procedures, random samples of surgical patients were obtained and the numbers of patients who showed no recurrence of the disease after a 1-year period were recorded. The data are shown in the table.

How large a sample would be necessary in order to estimate the difference in the true success rates to within .10 with 95% reliability?

48) The contingency table below shows the results of a random sample of 400 state representatives that was conducted to see whether their opinions on a bill are related to their party affiliations. Assuming the row and column classifications are independent, find an estimate for the expected cell count E_{22}.

A) 45.6

B) 93.84

C) 34.96

D) 55.2

49) A sports researcher is interested in determining if there is a relationship between the number of home team and visiting team wins and different sports. A random sample of 526 games is selected and the results are given below. Assuming the row and column classifications are independent, find an estimate for the expected cell count of cell E_{22}.

A) 25.9

B) 19.1

C) 144

D) 106