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Chapter 10: Q 13. (page 640)

Ban junk food! A CBS News poll asked 606 randomly selected women and 442

randomly selected men, “Do you think putting a special tax on junk food would encourage more people to lose weight?” 170 of the women and 102 of the men said “Yes.” A 99% confidence interval for the difference (Women – Men) in the true proportion of people in each population who would say “Yes” is −0.020to0.120. Does the confidence interval provide convincing evidence that the two population proportions are equal? Explain your answer.

Short Answer

Expert verified

It provides convincing evidence that two population proportions are equal.

Step by step solution

01

Given Information

It is given that at99%confidence interval, we got(-0.020,0.120).

02

Explanation

The given confidence interval has zero in it. Hence, it is likely that difference in proportion is zero and two population proportions are equal.

So, it is possible that population proportions are equal. Therefore, there is no convincing evidence that two population proportions are not equal.

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