[求助]一道GWD题啊。。

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 60 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?

A.      33 1/3%

B.       40%

C.      50%

D.      60%

E.       66 2/3%

完全没思路啊。。

confirm.

let the total number of passengers be X and the number of round trip passenger be Y,

20%X=40%Y=round trip w/ cars.

then X:Y=50%

我也觉得是50%

同意2楼答案，我做也是50%