Question

Given that $h=3a+28.6$
A pediatrician uses the model above to estimate the height $h$ of a boy, in inches, in terms of the boy's age $a$, in years, between the ages of $2$ and $5$. Based on the model, what is the estimated increase, in inches, of a boy's height each year?

• A. $3$
• B. $5.7$
• C. $9.5$
• D. $14.3$

Answer 1

The correct option is A $3$

Given model to estimate height is $h=3a+28.6$ in inches

At the age of $2$ years, the boy's height is $h_2=3\left(2\right)+28.6=6+28.6$ inches
At the age of $3$ years, the boy's height is $h_3=3\left(3\right)+28.6=9+28.6$ inches
Thus the difference in heights is $9+28.6-6-28.6=3$ inches