USA Today reports that the average expenditure on Valentine's Day was expected to be . Do male and female consumers differ in the amounts they spend? The average expenditure in a sample survey of male consumers was , and the average expenditure in a sample survey of female consumers was . Based on past surveys, the standard deviation for male consumers is assumed to be , and the standard deviation for female consumers is assumed to be . The value is .
Round your answers to decimal places.
a. What is the point estimate of the difference between the population mean expenditure for males and the population mean expenditure for females?