[Question]Hayden has a tank with a small hole in the bottom. The tank starts with 40 gallons of water. It loses 2 gallons of water per hour. Hayden does not add any water for the first two hours. He adds 1 gallon of water to the tank in hour three. He adds three gallons of water to the tank in the fourth hour. How much water is left in the tank at the end of the fourth hour?
[Answer]Over the four hours, the tank loses 2 * 4 = 8 gallons of water. Hayden adds a total of 1 + 3 = 4 gallons of water. At the end of the four hours, there is 40 - 8 + 4 = 36 gallons of water left in the tank. The answer is 36.

[Question]Charles is wondering how much chocolate milk he can make with all the supplies he finds in the fridge. He is going to keep drinking 8-ounce glasses until he uses up all the ingredients. Each glass must contain 6.5 ounces of milk and 1.5 ounces of chocolate syrup. If he has 130 ounces of milk and 60 ounces of chocolate syrup, how many total ounces ounce of chocolate milk will he drink?
[Answer]He has enough milk for 20 glasses of chocolate milk because 130 / 6.5 = 20. He has enough syrup for 40 glasses of chocolate milk because 60 / 1.5 = 40. He can make 20 glasses of chocolate milk because 20 < 40. He will drink 160 ounces of chocolate milk because 20 x 8 = 160. The answer is 160.

[Question]Sam has 18 cows. 5 more than half the cows are black. How many cows are not black?
[Answer]Half of the cows: 18 / 2 = 9. Black cows: 5 + 9 = 14. 18 - 14 = 4 cows. The answer is 4.

[Question]Chastity made 12 angel food cakes to give to friends. She placed the cakes in boxes, and then walked them out to her car. But she had forgotten her keys. So, she placed the boxes of cakes in one stack on the hood of her car, and then she ran back into the house to get her keys. But before she returned, a black crow came, landed on the stack of cakes, and knocked over half of the stack. When Chastity returned, she picked up half of the fallen cakes, which were not damaged, but the rest of the cakes were destroyed. How many cakes were destroyed?
[Answer]
There were 12 / 2 = 6 fallen cakes. Half of 6 fallen cakes were destroyed, for a total of 6 / 2 = 3 cakes. The answer is 3.