Answer
(a)
The median height of boys who are $50$ months old is approximately $40\text{ inches}$.
From the provided graph, check for the value of $y\text{-axis}$ for the corresponding value on
\[x\text{-axis}\]as $50$.
As shown by the blue line, it is $40\text{ inches}$.
(b)
Consider the provided formula,
$h=2.9\sqrt{x}+20.1$
Substitute $50$ for $x$ and find $h$.
That is.,
$h=2.9\sqrt{50}+20.1$
Now, use a calculator to find the value.
So, the value of $h$is $40.6\,\text{inches}$, which is close to $40$ as calculated above.
