Kyoko is a hard-working college junior. One Saturday, she decides to work nonstop until she has answered 200 practice problems for her chemistry course. She starts work at 8:00 AM and uses a table to keep track of her progress throughout the day. She notices that as she gets tired, it takes her longer to solve each problem.

8:00AM - 0

9:00AM - 80

10:00AM - 140

11:00AM - 180

12:00AM - 200

The marginal, or additional, gain from Kyoko's first hour of work, from 8:00 AM to 9:00 AM, is 80 problems.

The marginal gain from Kyoko's third hour of work, from 10:00 AM to 11:00 AM, is 40 problems.

Later, the teaching assistant in Kyoko's chemistry course gives her some advice. "Based on past experience," the teaching assistant says, "working on 30 problems raises a student's exam score by about the same amount as reading the textbook for 1 hour." For simplicity, assume students always cover the same number of pages during each hour they spend reading.

Given this information, in order to use her 4 hours of study time to get the best exam score possible, how many hours should she have spent working on problems, and how many should she have spent reading?

- 3 hours working on problems, 1 hour reading