Using the z-distribution, it is found that a sample of 171 should be selected.
<h3>What is a z-distribution confidence interval?</h3>
The confidence interval is:

The margin of error is:

In which:
is the sample mean.
is the standard deviation for the population.
For this problem, the parameters are:

Hence we solve for n to find the needed sample size.





n = 170.7.
Rounding up, a sample of 171 should be selected.
More can be learned about the z-distribution at brainly.com/question/25890103
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Answer:
pretty sure it's 15 but if you used my answer and it was wrong srr
5 times 40 times 49 equals 9800 because you do 5 time 4 and that's 20 and you add a 0 and you multiply by 49 to get 9800.
Are you solving for x or y?