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?
Give me a solution to this problem