With data from the 2009 National Health Interview Survey, the Centers for Disease Control and Prevention estimated that 33% of U.S. adults (18 and older) do not exercise. Is the percentage higher this year? Suppose we select a random sample of 100 adults (18 and older) this year. The conditions are met for use of a normal model, because we expect 33 (33% of 100) in the sample will not exercise and 67 (67% of 100) will. Both expected counts are greater than 10. We use a z-score and a standard normal curve to assess the evidence. (The standard error is 0.047.) Suppose that 38 of the 100 in our sample do not exercise. Which conclusion is supported by the data? Normal Distribution Calculator Drag the orange flag left or right to change the Z-score. Alternatively, enter a Z-score into the textbox and click enter. Enter