The manager of the local health club is interested in determining the number of times members use the weight room per month. She takes a random sample of 15 members and finds that over the course of a month, the average number of visits was 11.2 with a standard deviation of 3.2. Assuming that the monthly number of visits is normally distributed, which of the following represents a 95% confidence interval for the average monthly usage of all health club members?
A)	11.2 1.74
B)	11.2 1.77
C)	11.2 1.62
D)	11.2 1.83
Answer:C
The manager of the local health club is interested in determining the number of times members use the weight room per month. She takes a random sample of 15 members and finds that over the course of a month, the average number of visits was 11.2 with a standard deviation of 3.2. Assuming that the monthly number of visits is normally distributed, which of the following represents a 95% confidence interval for the average monthly usage of all health club members?
A)	11.2 1.74 B)	11.2 1.77 C)	11.2 1.62 D)	11.2 1.83