Walmart has an interest in monitoring the average backto-

school spending for grade-school students year to year.

The following table shows the average back-to-school spending of households randomly sampled in 2013 and 2014 along with the population standard deviations and sample sizes for each sample.

2013 2014 Sample mean $606.40 $548.72 Sample size 35 38 Population standard deviation $160 $150

a. Perform a hypothesis test using a = 0.10 to determine if the average household back-to-school spending in 2013 was different than it was in 2014.

b. Determine the p-value and interpret the results.

c. Verify your results using PHStat.

AppendixLO1