Rate, Time, and Distance

Question

On his way home from work Joe averaged only 20 mph. on his drive home, he averaged 40 mph. If the total travel time was 1 1/2 hours, how long did it take him to get to work?

Answer 1

The ratio of time is 2:1, that is, it takes twice as long to get to work as it is to get home.

x(2 + 1) = 90, because 1.5 hours equals 90 minutes. The 2+1 is the ratio times added together.

3x = 90 minutes

Divide both sides by 3:

x = 30

 

2 * 30 minutes + 1 * 30 minutes = 90 minutes

60 minutes + 30 minutes = 90 minutes

It takes Joe 60 minutes (or 1 hour) to get to work.