Hand Washing

In August 2005, researchers for the American Society for Microbiology and the Soap and Detergent Association monitored the behavior of more than 6300 users of public restrooms. They observed people in public venues such as Turner Field in Atlanta and Grand Central Station in New York City. They found that 2393 of 3206 men washed their hands, compared to 2802 of 3130 women.

a. For each gender, construct a 90 % confidence interval for the population proportion who wash their hands in public restrooms.

Round your answers to four decimal places.

Men: (______________, _____________)

Women: (____________, ___________)

b. Do these confidence intervals overlap? What does this suggest?

Round your answer to two decimal places, if required.

These confidence intervals do/not do overlap. This suggests that the population of men who wash their hands in public restrooms is at least ___________ percentage points less/more than the percentage of women who wash their hands in public restrooms.

c. Describe the populations you are willing to generalize these results to.

All American adults/     all American adults in the two cities surveyed in this study/        all adults