# Question: Suppose we are using the sample size formula in the

Suppose we are using the sample size formula in the box on page 313 to find the sample size needed to make the margin of error in a confidence interval for p equal to E. In each of the following situations, explain what value of p would be used in the formula for finding n:

a. We have no idea what value p is— it could be any value between 0 and 1.

b. Past experience tells us that p is no more than .3.

c. Past experience tells us that p is at least .8.

a. We have no idea what value p is— it could be any value between 0 and 1.

b. Past experience tells us that p is no more than .3.

c. Past experience tells us that p is at least .8.

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