Question: Maggie went to Lou's aquarium and saw 100 goldfish in the aquarium. She asked if she could take some home to care for, and she was allowed to catch half of them. While using a catching net, she caught 3/5 of the total number of goldfish she was allowed to take home. How many goldfish does Maggie remain with to catch to get the total number she was allowed to take home? Think carefully first, then make a decision:
Maggie was allowed to take half of the goldfish in the aquarium, a total of 1 / 2 * 100 = 50 goldfish. On her first catch, Maggie got 3 / 5 * 50 = 30 goldfish. To reach the number of goldfish she was allowed to take home, Maggie has to catch 50 - 30 = 20 more goldfish. So the answer is 20.