The average expenditure on Valentine's Day was expected to be 100.89 (USA Today, February 13, 2006). Do male and female consumers differ in the amounts they spend? The average expenditure in a sample survey of 52 male consumers was 132.5 , and the average expenditure in a sample survey of 38 female consumers was 63.34 . Based on past surveys, the standard deviation for male consumers is assumed to be 35, and the standard deviation for female consumers is assumed to be 14. The z value is 2.576.