Answer: 36 miles per hour (mph)
We have 12 miles traveled in 1/3 of an hour
Multiply both values by 3 so that the "1/3 hr" becomes "1 hr"
12*3 = 36
(1/3)*3 = 1
So you travel 36 miles in one hour, ie your speed is 36 miles per hour.
You can use this ratio to help
12 miles : 1/3 hr
3*(12 miles) : 3*(1/3) hr
36 miles : 1 hr
