On a certain transatlantic crossing, 20 percent of a ship’s passengers held round-trip tickets and also took their cars abroad the ship. If 50 percent of the passengers with round-trip tickets did not take their cars abroad the ship, what percent of the ship’s passengers held round-trip tickets?
Choose one.
A) 30%	B) 40%	C) 50%	D) 60%	E) 65%
Let T be the total number of passengers.   Let x be the number of people with round trip tickets.   0.2T had round trip tickets and took their cars.   0.5x had round trip tickets and took their cars.   0.5x = 0.2T   x = 0.4T   The answer is 40%.
<result>B</result>
On a certain transatlantic crossing, 20 percent of a ship’s passengers held round-trip tickets and also took their cars abroad the ship. If 50 percent of the passengers with round-trip tickets did not take their cars abroad the ship, what percent of the ship’s passengers held round-trip tickets?