# Megan finished 12 math problems in one hour. At this rate, how many hours will take her to complete 72 problems?

##### 3 Answers

Feb 1, 2016

#### Explanation:

Since

If

then

i.e.

Feb 1, 2016

Let's make proportion.

1 hour for 12 problems

x hours for 72 problems

x = 72/12 = 6

#### Explanation:

How ever you choose to approach this, you will find that they are all based on this ratio fact:

So the initial condition is:

This is presumed to be constant so,

let the unknown time (hours) be

Then multiply both sides by 72: