Suppose There Are 100 Firms in an Industry

Multiple Choice

Suppose there are 100 firms in an industry. If the leading firm has a 50 percent market share, the second largest firm has a market share of half the leader's, the third has a market share of half the second's, and the fourth largest has a market share of half the third's, what is the four-firm concentration ratio?

A) 6.25 percent
B) 100.00 percent
C) 75.50 percent
D) 93.75 percent
E) 99.75 percent