How many business students must be randomly selected to estimate the mean monthly earnings of business students at one college? We want 95% confidence that the sample mean is within $135 of the population mean, and the population standard deviation is known to be $538.

There are 61 business students must be randomly selected to estimate the mean monthly earnings of business students at one college.

Step-by-step explanation:

Since we have given that

mean = $135

Standard deviation = $538

At 95% level of confidence, z = 1.96

So, we get that

Hence, there are 61 business students must be randomly selected to estimate the mean monthly earnings of business students at one college.

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