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 35 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, develop a 95% confidence
interval
for the average monthly usage of all health club members.
Select one:
a. 11.2 ± 1.83
b. 11.2 ± 1.77
c. 11.2 ± 1.06
d. 11.2 ± 1.74