Question: A vinyl siding company claims that the mean time to install siding on a medium-size house is at most 20 hours with a standard deviation of 3.7 hours. A random sample of 40 houses sided in the last three years has a mean installation time of 20.8 hours. At the 0.05 significance level, can a claim be made that it takes longer on average than 20 hours to side a house?

a. State the null and alternate hypotheses.

b. State the decision rule.

c. Compute the value of the test statistic.

d. Compute the p-value.

e. What is your decision regarding the null hypothesis? Interpret the result.