The Canadian gumnut industry consists of 10 companies whose annual sales are as shown:

-What is the four-firm concentration ratio for this industry?

Question

The Canadian gumnut industry consists of 10 companies whose annual sales are as shown:
 
-What is the four-firm concentration ratio for this industry?

Quizplus · Accepted Answer

The four-firm concentration ratio is calculated by adding the market shares of the four largest firms in the industry. 
In this case, the four largest firms are A, B, C, and D with market shares of 20%, 10%, 15%, and 30%, respectively. 
Thus, the four-firm concentration ratio is 20% + 10% + 15% + 30% = 75%. 
Therefore, the correct answer is C.

The Canadian Gumnut Industry Consists of 10 Companies Whose Annual