In a certain parking lot, 2% of the cars are towed for parking illegally. However 90% of the cars which are parked illegally are not towed. What percentage of cars in the parking lot are parked illegally?  Choices: A) 10% B) 12% C) 16% D) 18% E) 20%
Let x be the number of cars and let y be the number of cars parked illegally.   2%*x = 10%*y   y/x = 1/5 = 20%   The answer is 20%.
<result>E</result>
In a certain parking lot, 2% of the cars are towed for parking illegally. However 90% of the cars which are parked illegally are not towed. What percentage of cars in the parking lot are parked illegally?