[Question]: Matt's entire family was going to spend the week at the lake house for vacation. Matt's family included his mom, dad, his older brother and his wife and their 4 kids. His Uncle Joe and his wife were also coming and would bring their 3 kids. The house only sleeps 4 people. Everyone else would sleep 2 to a tent outside. How many tents would they need?
[Answer]: We need to add Matt's entire family together so 1 + 2 + 2 + 4 + 2 + 3 = 14. Only 4 people could sleep in the house so 14 - 4 = 10 people would sleep in a tent. Each tent sleeps 2 people and there were 10 people left so 10 / 2 = 5 tents were needed.
So the answer is 5.

[Question]: Isabel has some money in her piggy bank. She spent half the amount and bought a toy. She then spent half of the remaining money and bought her brother a book. If she has $51 left, how much money, in dollars, did she have at first?
[Answer]: After buying the toy, Isabel has 51 * 2 = 102 dollars left. Isabel had 102 * 2 = 204 dollars at first.
So the answer is 204.

[Question]: 1,800 fish swim westward, 3,200 swim eastward, and 500 swim north. What is the number of fish left in the sea, if fishers catch 2/5 of the fish that swam eastward and 3/4 of the fish that swam westward?
[Answer]:
When fishers caught 3 / 4 of the fish that swam westward, their total number reduced by 3 / 4 * 1800 fish = 1350. The total number of fish that remained from the total number that swam eastward is 1800 fish - 1350 fish = 450 fish. If fishers caught 2 / 5 of the fish that swam eastward, their total number reduced by 2 / 5 * 3200 fish = 1280 fish. 3200 fish - 1280 fish = 1920 fish remained in the sea from the number that swam westward. The total number of fish in the sea after fishers caught some is 500 of the number that went north + 450 of the fish that swam westward + 1920 of the fish that swam eastward = 2870 fish.
So the answer is 2870.