Chapter 7, Problem 19RE

To determine

To determine when the BMI for males exceeds the BMI for females

Answer to Problem 19RE

Males BMI exceeds female BMI after age 20

Explanation of Solution

Given:

The given equations are:

  $B\text{=0}\text{.77}a\text{+11}\text{.7}$

  $B\text{=0}\text{.68}a\text{+13}\text{.5}$

Consider the BMI for males

$B\text{=0}\text{.77}a\text{+11}\text{.7}$

Consider the BMI for females

$B\text{=0}\text{.68}a\text{+13}\text{.5}$

Here $a$ is the age in years and $B$ is the BMI in $kg/m^2$

Consider the two graphs of above functions by taking $a$ on $x-axis$ and B on $y-axis$

Graphs of two functions is shown below

  

Two curves intersect at $a=20$

For $a>20$ male BMI exceeds female BMI.

Thus males BMI exceeds female BMI after age 20