A Department Store Believes That Telephone Calls Come into the Switchboard

Essay

A department store believes that telephone calls come into the switchboard at 10-minute intervals, according to a Poisson distribution. Before ordering new equipment, the store wishes to determine whether the Poisson model is a valid assumption. Records on the number of calls received were kept for a random selection of 150 ten-minute intervals. The results are shown below.
a. What is the average number of calls during these ten-minute intervals?
b. Generate the expected number of calls using a Poisson probability table.c. Give the null and alternative hypotheses for the appropriate test.
d. Determine the number of degrees of freedom for this test.
e. Calculate the value of the test statistic.f. Determine the p-value and state whether or not the Poisson model is a valid model for the phone calls?