Question

A study by the national center for health statistics found that the BMI of American young women (ages 20-29) has a mean of 26.8 and a standard deviation of 7.4. Circle the best answer.
a. Using the 68-96-99.7% rule, approximately 84% of this population would have a BMI that is more than 19.4

b. The national center for health defines a person with a BMI that is in the lower 13% of the population to be underweight. According to this definition, young female with a BMI of 19.6 is underweight.

c. The national center for health defines a person with a BMI associated with a z-score of 0.43 or more to be overweight. According to this definition approximately a person with a BMI of 31.0 is overweight

d. Both (a) and (b) are true.

e. Both (a) and (c) are true.

Answer 1

(a) A BMI of 19.4 is one standard deviation below the mean. Therefore using the empirical rule answer (a) is true.

(b) A BMI of 19.6 is above the lower 16% of the population. Therefore answer (b) is false.

(c) A z-score of 0.43 applies to a BMI of 30. Therefore answer (c) is true.

(d) False.

(e) True.

The best answer is (e).