Question

In: Statistics and Probability

A survey of 25 randomly selected customers found the ages shown (in years). The mean is...

A survey of 25 randomly selected customers found the ages shown (in years).

The mean is 32.64 years and the standard deviation is 9.97 years.

​a) What is the standard error of the​ mean?

​b) How would the standard error change if the sample size had been

400

instead of

25​?

​(Assume that the sample standard deviation​ didn't change.)

Solutions

Expert Solution

Solution :

Given that ,

mean = = 32.64

standard deviation = = 9.97

n = 25

standard error = =  / n =9.97 / 25=1.994

= 1.994

(B)

n = 400

standard error = =  / n =9.97 / 400=0.4985

= 0.4985

orchestra answered 2 years ago
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