Banking fees have received much attention during the recent economic recession as bankslook for ways to recover from the crisis. A sample of 31 customers paid an average fee of $11.53 permonth on their checking accounts. Assume the population standard deviation is $1.50. Calculatethe margin of error for a 90% confidence interval for the mean banking fee.

The margin of error for a 90% confidence interval for the mean banking fee is of $0.44.

Step-by-step explanation:

We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Z-table as such z has a p-value of .

That is z with a pvalue of , so Z = 1.645.

Now, find the margin of error M as such

In which is the standard deviation of the population and n is the size of the sample.

Sample of 31:

This means that

Assume the population standard deviation is $1.50.

This means that

Calculate the margin of error for a 90% confidence interval for the mean banking fee.

The margin of error for a 90% confidence interval for the mean banking fee is of $0.44.