Solve graphically and find one possible solution for this problem.

It takes Mark 75 minutes and 3 cans of paint to finish painting the rooms in a house, and it takes him 15 minutes and 1 can of
paint to finish painting the ceilings. Mark is required to spend more than 300 minutes to paint the rooms and ceilings of a house, and he can use at most 20 cans of paint.