Ann and Joe’s father donated $3 for every lap they swam in a swim-a-thon. Ann swam 21 laps, and Joe swam 15 laps. Find the amount of money their father donated.

Darian wants to build a regulation size pool table that is 9 feet in length.he plans he ordered are 18 by 36 inches. what is the scale factor of the dilation he must use to build a regulation pool table

At a book fair, joe bought 24 books at 3 for $5 and had $2 left. how much money did he have at first?

If x varies directly as y, and x = 7.5 when y = 10, find x when y = 4