This is a proportion problem. 2.5 miles is to 50 minutes as 1 mile is to x.
x= # minutes to walk 1 mile
2.5 miles/50 min= 1 mile/ x
cross multiply
(2.5 * x) = (50 * 1)
2.5x=50
divide both sides by 2.5
20= x
She can walk 1 mile in 20 minutes so B) 20m is the answer.
Hope this helps! :)
