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Chapter 8: Q 8. (page 507)

Fun size candyA candy bar manufacturer sells a “fun size” version that is advertised to weigh 17grams. A hungry teacher selected a random sample of 44fun size bars and found a 95%confidence interval for the true mean weight to be 16.945grams to 17.395grams.

a. Does the confidence interval provide convincing evidence that the true mean weight is different than 17grams? Explain your answer.

b. Does the confidence interval provide convincing evidence that the true mean weight is 17grams? Explain your answer.

Short Answer

Expert verified

a. There is no convincing evidence that true mean is different from 17grams.

b. There is no convincing evidence due the presence of other values for true mean also.

Step by step solution

01

Given Information

It is given that for 95%confidence interval, true mean weight is (16.945grams-17.395grams)

02

a. Whether the confidence interval provides convincing evidence that the true mean weight is different than 17 grams.

As confidence interval has 17grams.

True mean weight is 17grams is likely.

Hence, there is no evidence that true mean weight is different from17grams.

03

b. Whether the confidence interval provides convincing evidence that the true mean weight is 17 grams.

From above, it is clear that true mean weight is 17grams.

Also, all weight between (16.945grams-17.395grams)are equally like to be the true mean. True mean weight is not surely 17grams.

Hence, there is no convincing evidence.

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Most popular questions from this chapter

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