[Question]: Jenny is working on a school project. She spends 10 hours doing research for the project and 2 hours writing a proposal. If she has 20 hours total to work on the project, how many hours does she have left to write her report?
[Answer]: So far, Jenny has spent 10 + 2 = 12 hours on the project. Thus, she has 20 - 12 = 8 hours to write her report.
So the answer is 8.

[Question]: 24 gallons per second of water flows down a waterfall. If you have an empty basin that can hold 260 gallons of water. The basin leaks water at 4 gallons per second. how long would it take to fill the basin with water from the waterfall in seconds?
[Answer]: 24 gallons in minus 4 gallons out is 24 - 4 = 20 gallons per second. 260 gallons divided by 20 gallons per second 260 / 20 = 13 seconds.
So the answer is 13.

[Question]: A passenger train transports passengers between two stations located in two separate cities. On a particular day, the train carried 100 passengers from one station to the other one way, and on the return trip carried 60 passengers. If the train made three more round trips that day, taking the same number of people as the first trip in each trip, calculate the total number of passengers transported between both stations?
[Answer]:
The total number of people transported in the first trip is 100 one way + 60 on the return trip = 160 people. If the train made three more round trips that day carrying the same number of passengers in each trip as the first, it carried a total of 3 * 160 = 480 in all three round trips. In total, the train carried 160 + 480 = 640 people over all its trips that day.
So the answer is 640.