A political candidate has asked you to conduct a poll to determine what percentage of people support her. If the candidate only wants a 5% margin of error at a 99% confidence level, what size of sample is needed

A sample size of 664 is needed.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of , and a confidence level of , we have the following confidence interval of proportions.

In which

z is the zscore that has a pvalue of .

The margin of error is:

99% confidence level

So , z is the value of Z that has a pvalue of , so .

If the candidate only wants a 5% margin of error at a 99% confidence level, what size of sample is needed

A sample size of n is needed.

n is found when M = 0.05.

We have no estimate, so we use . Then

Rounding up

A sample size of 664 is needed.

the answer is 24

step-by-step explanation: