In 1930, the Average Size of a Public Restroom Was

Short Answer

In 1930, the average size of a public restroom was 172 square feet. By 1990, due to federal disability laws, the average size had increased to 471 square feet. Suppose that a design team believes that this standard has increased from the 1990 level. They randomly sample 23 public restrooms in a major midwestern city and obtain a mean square footage of 498.78 with a standard deviation of 46.94. Test the hypotheses at α = .001 using the critical value rule.