10.16 Housework for women and men Do women tend to spend more time on housework than men? If so, how much more? Based on data from the National Survey of Families and Households, one study reported the results in the table for the number of hours spent in housework per week. (Source: Data from A. Lincoln, Journal of Marriage and Family, vol. 70, 2008, pp. 806–814.)

Housework Hours Gender Sample Size Mean Standard Deviation Women 476 33.0 21.9 Men 496 19.9 14.6

a. Based on this study, calculate how many more hours, on the average, women spend on housework than men.

b. Find the standard error for comparing the means. What factor causes the standard error to be small compared to the sample standard deviations for the two groups?

c. Calculate the 95% confidence interval comparing the population means for women and men. Interpret the result including the relevance of 0 being within the interval or not. (Hint: For such large sample sizes, the t-score is practically identical to a z-score.)

d. State the assumptions upon which the interval in part c is based.