10.2 More on BMI and physical activity. Refer to Examples 10.3 (page 562) and 10.4 (page 564).

  1. (a) What is the predicted BMI for a woman who averages 9500 steps per day?

  2. (b) If an observed BMI at x = 9.5 were 24.3, what would be the residual?

  3. (c) Suppose that you wanted to use the estimated population regression line to examine the predicted BMI for a woman who averages 4000, 10,000, or 16,000 steps per day. Discuss the appropriateness of using the least-squares equation to predict BMI for each of these activity levels.