A child was 20 inches tall at birth and 42 inches tall at age 4. What was the average rate of change in the child's height per year from birth to age 4?

Answer

5.5 inches per year

Rationale

Change in height from birth to age 4: 42 - 20 = 22 inches over 4 years. 22 / 4 = 5.5 inches per year.

Answer choices

• A. 5.5 inches per year

• B. 6 inches per year

• C. 6.5 inches per year

• D. 3 inches per year