At the Punjab Bakery, two workers can decorate 14 cakes in an hour and three workers can decorate 18 cakes in an hour. The marginal product of the third worker is
A) 18 cakes, and the average product for three workers is 6 cakes.
B) 4 cakes, and the average product for three workers is 6 cakes.
C) 9 cakes and is equal to the average product.
D) 32 cakes, and the average product for three workers is 9 cakes.
E) 6 cakes, and the average product for three workers is also 6 cakes.

Question

Quizplus · Accepted Answer

Let MP3 be the marginal product of the third worker and AP3 be the average product of three workers. 
We can create the following system of equations: 
2W = 14 ---> W = 7 cakes (where W is the marginal product of two workers) 
3X = 18 ---> X = 6 cakes (where X is the marginal product of three workers) 
2W/2 = 7/2 = 3.5 cakes (where W/2 is the average product of two workers) 
3X/3 = 6/3 = 2 cakes (where X/3 is the average product of three workers) 
Using the formula for marginal product, we have: 
MP3 = X - (2X/3) = 4/3 cakes 
Therefore, the answer is B because MP3 is 4 cakes and AP3 is 6 cakes.

At the Punjab Bakery, Two Workers Can Decorate 14 Cakes