2014 AMC 8 Problem 5

Margie's car can go 32 miles on a gallon of gas, and gas currently costs 4 per gallon. How many miles can Margie drive on 20?

\textbf{(A) }64\qquad\textbf{(B) }128\qquad\textbf{(C) }160\qquad\textbf{(D) }320\qquad\textbf{(E) }640

Full credit goes to MAA for authoring these problems. These problems were taken on the AOPS website.