210 college students were asked in a survey if they preferred Windows or Mac brand computers. 60 Students claimed that they preferred Mac to Windows brand computers. One third as many of the students who preferred Mac to Windows, equally preferred both brands. 90 of the students had no preference. How many of the students in the survey preferred Windows to Mac brand computers?  Choose the correct choice.
A) 25
B) 40
C) 50
D) 60
E) 75

Rationale: 120 = 60 ( mac ) + x ( window ) + 20 ( both ) = > x = 40 answer : b
Answer: B