The Centers for Disease Control (CDC)would like to test the hypothesis that the proportion of obese adults in the U.S. has increased this year when compared to last year. A random sample of 125 adults this year found that 56 were obese. Last year, a random sample of 140 adults found that 42 were obese. If Population 1 is defined as this year and Population 2 is defined as last year, the test statistic for this hypothesis test would be ______ .

Question

Quizplus · Accepted Answer

The test statistic for comparing two proportions is calculated using the formula for a z-test. The correct calculation involves determining the difference between the sample proportions and then dividing by the standard error of the difference in proportions. The positive value indicates an increase in the proportion of obese adults, which aligns with the hypothesis being tested.

The Centers for Disease Control (CDC)would Like to Test the Hypothesis