Give the step-by-step reasoning process and then the final answer. It's exam season and Tristan has several exams to prepare for. On Monday, he studies for 4 hours then studies for twice this long on Tuesday. On Wednesday, Thursday, and Friday he studies for 3 hours each day. He wants to study for a total of 25 hours over the week and divides the remaining amount of study time evenly between Saturday and Sunday. How many hours does Tristan spend studying on Saturday?
On Tuesday, Tristan studies twice as long as he did on Monday and this amounts to 4 hours * 2 = 8 hours. So in the first 5 days of the week, he studies for a total of 4 hours Monday + 8 hours Tuesday + 3 hours Wednesday + 3 hours Thursday + 3 hours Friday = 21 hours. He therefore has 25 planned hours 21 used hours = 4 hours left to study. As he splits his time evenly over 2 days, he spends 4 hours / 2 = 2 hours studying on Saturday.
The final answer: 2.