jan can run 3 miles in 1/4 hour. how long can jan run for one hour

Question

You have to do a a proportion. 

Answer 1

To set up a proportion, I would do the following:

3 miles/1/4 hour = x miles/1 hour     

Cross multiply

(1/4)x = 3       Multiply both sides by 4.

x = 12 miles/1 hour

Answer 2

in 1/4 hour  : 3 miles

 

in 1 hour : 12 miles --------------multiply both side with 4