Question

A truck driver starts driving his truck at 2:00 and drives for 45 minutes at 45 miles per hour. 3. at what time will he have traveled 30 miles? 4. what is his speed in miles per minute?

Answer 1

If you travel at a constant speed, you follow this formula:

$s = vt$

where s is the space traveled, v is the speed and t is the time passed. Knowing the speed and the desired space, we can solve the equation for the time:

$t = \dfrac{s}{v}$

Plug your values:

$t = \dfrac{30}{45} = \dfrac{2}{3}$

And two-thirds of an hour are 40 minutes.

To convert his speed in miles per minutes, you only need to use that one hour is composed of 60 minutes:

$\dfrac{45 \text{ miles}}{1\text{ hour}} = \dfrac{45 \text{ miles}}{60\text{ minutes}} = \dfrac{3 \text{ miles}}{4 \text{ minutes}} = 0.75$ miles per minute