Question

At a rate of 36 miles per hour, it takes Henry 15 minutes to drive from the library to his house. Show how to find the distance that Henry traveled. Include units in your calculation.

Answer 1

This is applying the formula
$distance=rate*time$

We have a slight problem, though, because we are measuring rate in miles per hour, and we are measuring time in minutes. To make this problem solvable, we need to convert to either miles per minute or convert the time to hours. I'm going to convert the 15 minutes into hours:
$15min*\frac{1 hour}{60 min}=\frac{1}{4}hour$

Now that all of the units match, we have:
$distance=36\frac{mi}{hr}*\frac{1}{4}hr$

You can finish from there I'm sure.