Question

4. A decision at the margin Nick is a hard-working college senior. One Saturday, he decides to work nonstop until he has answered 250 practice problems for his math course. He starts work at 8:00 AM and uses a table to keep track of his progress throughout the day. He notices that as he gets tired, it takes him longer to solve each problem. Time Total Problems Answered 8:00 AM 9:00 AM 100 10:00 AM 175 11:00 AM 225 250 Noon Use the table to answer the following questions. The marginal, or additional, gain from Nick's first hour of work, from 8:00 AM to 9:00 AM, is problems. The marginal gain from Nick's third hour of work, from 10:00 AM to 11:00 AM, is problems. Later, the teaching assistant in Nick's math course gives him some advice. "Based on past experience," the teaching assistant says, "working on 62.5 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.

Answer 1

Solution:-

Marginal Gain of problems is as Follows:-

Time	Total Problems Answered	Marginal Gain
8:00 AM	0	-
9:00 AM	100	100
10:00 AM	175	75
11:00 AM	225	50
Noon	250	25

The marginal gain from Nick's first hour of work from 8:00 AM - 9:00A.M. = (100 – 0) = 100

The marginal gain from Nick's 3rd hour of work from 10:00 AM – 11:00 A.M. = (225 – 175) = 50

Since reading textbook = 62.5 problems.

Thus first hours of solving problem solves 100 problems > reading 1 hour textbook

Second hour solves 75 problems <reading 1 hour textbook

Thus 1hour should be used for problem solving and 3hours of reading textbooks.

Correct Option is (B)