Suppose that when a coal-mining firm hires one,two,three,four,or five workers,the corresponding total output is 10,15,19,22,or 24 tonnes of coal,respectively.The marginal product of the third worker is _____ tonnes of coal.
A) 3
B) 4
C) 15
D) 19

Question

Quizplus · Accepted Answer

The marginal product of a worker is the additional output produced when one more worker is hired. 
Therefore, the marginal product of the third worker can be calculated by finding the difference between the total output produced with three workers and the total output produced with two workers:
Marginal product of the third worker = Total output with three workers - Total output with two workers
= 19 - 15
= 4
Therefore, the marginal product of the third worker is 4 tonnes of coal. 
The answer is B.

Suppose That When a Coal-Mining Firm Hires One,two,three,four,or Five Workers,the