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Chapter 10: Q. AP3.31 (page 705)

A researcher wants to determine whether or not a 5-week crash diet is effective over a long period of time. A random sample of 15five-week crash dieters is selected. Each person’s weight (in pounds) is recorded before starting the diet and 1year after it is concluded. Do the data provide convincing evidence that 5-week crash dieters weigh less, on average, 1year after finishing the diet?

Short Answer

Expert verified

The diet does not have a long-term effect.

Step by step solution

01

Step 1 -  Given information:

We have been given that:

Data of a 5-week crash diet.

02

Step 2 -  Explanation:

H0 is being tested: μb=μaversus H1:μb=μa, where b is the mean of the before weights and an is the mean of the after weights The following table shows the changes between before and after weights: n=15 sample size,m=54/15=3

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