Answer:
0.998 is the probability that the average money spent by a sample of 40 shoppers is within $10 of the actual population mean.
Step-by-step explanation:
We are given the following information in the question:
Standard Deviation, σ = $21.51
We are given that the distribution of average money spend is a bell shaped distribution that is a normal distribution.
Formula:
We have to find:
P( average money spent is within $10 of the actual population mean.)
Calculation the value from standard normal z table, we have,