Question

A decision at the margin ew is a hard-working college sophomore. One Saturday, he de cides to c work nonstop until he has answered 200 practice problems for his economics course. He starts work at 8:00 AM and uses a table to k that as he gets tired, it Time Total Problems Answered 8:00 AM 9:00 AM 10:00 AM 11:00 AM Noon 80 140 180 200 Use the table to answer the following questions The marginal, or additional gain fr m Andrew's second hour of work, from 9:00 AM to 10:00 AM is The marginal gain from Andrew's fourth hour of work, from 11:00 AM to noon, is﹂-problems. blems. Later, the teaching assistant in Andrew's economies course gives him some advice. "Based on past experience," the teaching assistant says, "working on 50 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 his 4 hours of study time to get the best exam score possible, how many hours should he have spent working on problems, and how many should he have spent reading? 0 hours working on problems, 4 hours reading 1 hour working on problems, 3 hours reading 2 hours working on problems, 2 hours reading 3 hours working on problems, 1 hour reading

Answer 1

The marginal gain for each hour would be the difference between the total problems answered at the end of that hour and the total problems answered at the end of the previous hour.

1) The marginal gain for the second hour of work, 9:00 AM to 10 AM is 140 - 80 problems=60 problems

2) The marginal gain for the fourth hour of work, 11:00 AM to noon is 200 - 180 problems=20 problems


3) c) 2 hours working on problems, 2 hours reading.

One hour of reading is equal to 50 problems answered. So if the problems answered in one hour is more than 50, than Andrew is better off answering problems. If the problems answered is less than 50, than Andrew would be better of reading. From 8 AM to 9 AM, he can answer 80 which is higher than 50. He should answer problems for the first hour. From 9 AM to 10 AM, he can answer 60 problems which is also greater than 50, so he should answer questions for the second hour also.

For the third and fourth hours the problems answered is less than 50, so he is better off reading. So he should spend the first 2 hours answering problems and the next 2 hours reading to get the maximum benefit.