12.) Your mother gave you $13.32 with which to buy a present. This covered 3/5 of the cost. How much did the present cost?

13.) If the weight of a package is multiplied by 5/7 the result is 40.5 pounds. Find the weight of the package.

14.) A stray dog ate 12 of your muffins. That was 3/10 of all of them! With how many did you start?