On a certain transatlantic crossing, 20 percent of a ship’s passengers held round-trip tickets and also took their cars aboard the ship. If 60 percent of the passengers with round-trip tickets did not take their cars aboard the ship, what percent of the ship’s passengers held round-trip tickets?
(A) 33 1/3%
(B) 40%
(C) 50%
(D) 60%
(E) 66 2/3%
Let the total # of passengers be 100.
Now, 20 passengers held round-trip tickets AND cars.
As 60% of the passengers with round-trip tickets did not take their cars then 40% of the passengers with round-trip tickets did take their cars, so # of passengers with round-trip tickets AND cars is 40% of the passengers with round-trip tickets.
If we take # of the passengers with round trip tickets to be x
x
then we’ll have 0.4x=20
0.4
x
=
20
--> x=50
x
=
50
.
Answer: C.
can anyone help to explain this question.