Given that,
Distance covered by Charlie = 208 miles in 4 hours.
It is required to find the equation that shows the relationship between driving hours (h) and miles driven (m).
The formula for speed is given by :
speed = distance/time
Here, distance = 208 miles and time = 4 hours
So,
[tex]s=\dfrac{d}{t}[/tex]
Putting the values,
[tex]s=\dfrac{208\ \text{miles}}{4\ \text{hours}}\\\\s=52\ mph[/tex]
So, the speed of Charlie is 52 mph.