Question

1/10 of the cost of a class trip can be raised by a sandwich sale. Another 3/10 of the cost can be raised by a car wash. Will 4 sanwich sales and 2 car washes raise the required amount of money?

Answer 1

Yes. Assume the cost of the class trip to be 100 bucks. Then A sandwich sale raises x times 10 (1/10th). The car wash raises y times 30. But x=4 and y=2; therefore the sandwich raises 40 bucks whereas the wash raises 2*30=60 bucks. In total 100 bucks!