Question

In a survey of 495 potential jurors, one study found that 345 were regular watchers of at least one crime-scene forensics television series.

(a) Assuming that it is reasonable to regard this sample of 495 potential jurors as representative of potential jurors in the United States, use the given information to construct a 95% confidence interval for the true proportion of potential jurors who regularly watch at least one crime-scene investigation series. (Use Table 3 in Appendix A. Give the answer to three decimal places.)

( , )

(b) Would a 99% confidence interval be wider or narrower than the 95% confidence interval from Part (a)?

widernarrower

Answer 1

Refer Standard normal table/Z-table or use excel function "=NORM.S.INV((1-0.025))" to find the Z-value.

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As the level of confidence increases from 95% to 99%, The confidence interval becomes wider.