# Question: A random sample of 20 purchases showed the following amounts

A random sample of 20 purchases showed the following amounts (in $):

The mean was $45.26 and the standard deviation was $20.67.

a) What is the standard error of the mean?

b) How would the standard error change if the sample size had been 5 instead of 20? (Assume that the sample standard deviation didn’t change.)

The mean was $45.26 and the standard deviation was $20.67.

a) What is the standard error of the mean?

b) How would the standard error change if the sample size had been 5 instead of 20? (Assume that the sample standard deviation didn’t change.)

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