Find the sample size necessary to estimate the mean IQ score

Find the sample size necessary to estimate the mean IQ score of statistics students such that it can be said with

95% confidence that the sample mean is ±22 IQ points of the true mean. Assume that the standard deviation is

19 and determine the required sample size.

N=....

Over here we have the margin of error = 22

n = sample size = { z * SD / m }²

SD = 19

z = 1.96 for 95% confidence interval

m = 22

Thus,

n = 2.86 students

or n = 3 students.

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