The amount of time a bank teller spends with each customer has a population
mean of 3.10 minutes and standard deviation of 0.40 minute. If a random sample
of 16 customers is selected,
a) what assumption must be made in order to solve parts (b) and (c)?
b) what is the probability that the average time spent per customer will be at
least 3 minutes?
c) there is an 85% chance that the sample mean will be below how many
minutes?
d) If a random sample of 64 customers is selected, there is an 85% chance that
the sample mean will be below how many minutes?
1 answer
The manager of Lone Star Restaurant believes that the average wait time of the Saturday evening meal is 30 minutes. To test this belief, the manager selects 50 customers at random and computes the average wait time to be 34 minutes. Assume a population standard deviation of 12 minutes.