Fowle Marketing Research, Inc., bases charges to a client on the assumption that telephone surveys can be completed in a mean time of 15 minutes or less. If a longer mean survey time is necessary, a premium rate is charged. Suppose a sample of 35 surveys produces the data in the Microsoft Excel Online file below. Use a known ? = 4 minutes. Is the premium rate justified?

Formulate the null and alternative hypotheses for this application.

H₀: ?

greater than or equal to 15, greater than 15, less than or equal to 15, less than 15, equal to 15, not equal to 15

H_a: ?

greater than or equal to 15, greater than 15, less than or equal to 15, less than 15, equal to 15, not equal to 15

Compute the value of the test statistic (to 2 decimals).

What is the p-value (to 4 decimals)?

Using ? = .01, is a premium rate justified for this client?