A newspaper reports that the average expenditure on Valentine'sDay is $100.89. Do male and female consumers differ in the amountsthey spend? The average expenditure in a sample survey of 40 maleconsumers was $135.67, and the average expenditure in a samplesurvey of 30 female consumers was $61.64. Based on past surveys,the standard deviation for male consumers is assumed to be $35, andthe standard deviation for female consumers is assumed to be$20.
(a)
What is the point estimate (in dollars) of the differencebetween the population mean expenditure for males and thepopulation mean expenditure for females? (Use male ? female.)
$
(b)
At 99% confidence, what is the margin of error (in dollars)?(Round your answer to the nearest cent.)
$
(c)
Develop a 99% confidence interval (in dollars) for thedifference between the two population means. (Use male ? female.Round your answer to the nearest cent.)
$ to $
