The ratio of buses to cars on River Road is 1 to 3. If there are 40 fewer buses than cars on River Road, how many cars are on River Road? Choose the correct choice from the following answers
A) 60	B) 75	C) 85	D) 95	E) 105

Rationale: "b / c = 1 / 3 c - b = 40 . . . . . . . . . > b = c - 40 ( c - 40 ) / c = 1 / 3 testing answers . clearly eliminate bcde put c = 60 . . . . . . . . . > ( 60 - 40 ) / 60 = 20 / 60 = 1 / 3 answer : a"
Answer: A