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Chapter 10: Q 6. (page 639)

Broken crackers We don鈥檛 like to find broken crackers when we open the package. How can makers reduce breaking? One idea is to microwave the crackers for 30seconds right after baking them. Randomly assign 65newly baked crackers to the microwave and another 65to a control group that is not microwaved. After 1day, none of the microwave group were broken and 16of the control group were broken. Let p1be the true proportions of crackers like these that would break if baked in the microwave and p2be the true proportions of crackers like these that would break if not microwaved. Check if the conditions for calculating a confidence interval forp1-p2met.

Short Answer

Expert verified

It is not suitable to find confidence interval forp1-p2

Step by step solution

01

Given Information

It is given that n1=65

x1=0

n2=65

x2=16

02

Explanation

Testing three conditions for hypothesis test:

Random: As they are assigned, it is satisfied.

Independent: Since all data values in population and used sample, this condition is satisfied.

Normal: There are zero success in first sample, it is not at least 10.

As normal condition is not met, we cannot find confidence intervalp1-p2

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Most popular questions from this chapter

Which inference method?

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b. fail to reject H0because 0.048<伪=0.05. There is not convincing evidence of a difference in the average time spent on extracurricular activities by students in the suburban and city school districts.

c. fail to reject H0because0.048<伪=0.05. There is convincing evidence that the average time spent on extracurricular activities by students in the suburban and city school districts is the same.

d. reject H0because 0.048<伪=0.05. There is not convincing evidence of a difference in the average time spent on extracurricular activities by students in the suburban and city school districts.

e. reject H0because 0.048<伪=0.05 . There is convincing evidence of a difference in the average time spent on extracurricular activities by students in the suburban and city school districts.
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