Reasoning and 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: 36
What was the question?
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?

Reasoning and answer: If she invited 20 friends, then the number of friends who came with one more person is 1 / 2 * 20 = 10. If the 10 friends came with 10 more people, the total number of guests becomes 20 + 10 = 30 guests. If you add Ashley, the total number of people in the party is 30 + 1 = 31 people.
The answer: 31
What was the question?
Question: Ashley had a birthday party and invited 20 of her friends, telling them to each invite one more person to attend the party. If half the number of the invited guests each came with one more person, what's the total number of people at the party, including Ashley?

Reasoning and answer: The total distance Terese runs is 4.2 + 3.8 + 4.4 + 3.6 = 16 miles. Therefore, she runs with an average distance of 16 / 4 = 4 miles.
The answer: 4
What was the question?
Question:
Terese thinks that running various distances throughout the week can make one healthy. On Monday, she runs 4.2 miles; Tuesday, 3.8 miles; Wednesday, 3.6 miles; and on Thursday, 4.4 miles. Determine the average distance Terese runs on each of the days she runs.