# Question

As mentioned in Exercise 7.33, among college students who hold part-time jobs during the school year, the distribution of the time spent working per week is approximately normally distributed with a mean of 20.20 hours and a standard deviation of 2.60 hours. Find the probability that the average time spent working per week for 18 randomly selected college students who hold part-time jobs during the school year is

a. Not within 1 hour of the population mean

b. 20 to 20.50 hours

c. At least 22 hours

d. No more than 21 hours

a. Not within 1 hour of the population mean

b. 20 to 20.50 hours

c. At least 22 hours

d. No more than 21 hours

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