Problem:
Ray's car averages 40 miles per gallon of gasoline, and Tom's car averages 10 miles per gallon of gasoline. Ray and Tom each drive the same number of miles. What is the cars' combined rate of miles per gallon of gasoline?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
Let equal the distance traveled by each car. Then Ray's car uses gallons of gasoline and Tom's car uses gallons of gasoline. The cars combined miles per gallon of gasoline is
The problems on this page are the property of the MAA's American Mathematics Competitions