One day a car rental agency rented 2/3 of its cars, including 3/5 of its cars with CD players. If 3/4 of its cars have CD players, what percent of the cars that were not rented had CD players? Answers
A) 10 % B) 35 % C) 45 % D) 66.7 % E) 90 %

Rationale: let us try to solve this by getting some number for total cars . let there be 3,4 and 5 = 60 cars . . . ( we have taken denominators of 2 / 3,3 / 4 and 3 / 5 least common number ) . 2 / 3 ( 60 ) = 40 cars . . . total rented cars , then 1 / 3 ( 60 ) = 20 cars were not rented . 3 / 4 ( 60 ) = 45 cars with cd players . . . total cdp cars now 3 / 5 ( 3 / 4 ) = 3 / 5 ( 45 ) = 27 cdp cars and these are cars that we rented . non rented cdp = total cdp - rented cdp = 45 - 27 = 18 . 18 / 20 = 90 % . answer : e
Answer: E