PP2-PS-160

[vantreal]

160. 16619-!-item-!-187;#058&011092
An automobile manufacturer offers a station wagon with either a 6-cylinder engine or a 4-cylinder engine and with either a manual transmission or an automatic transmission. A trailer hitch is also offered, but only on a station wagon with a 6-cylinder engine. How many combinations of the five options listed does the manufacturer offer for its station wagon?

(A) 3
(B) 4
(C) 5
(D) 6
(E) 8

Ans: (D)

想請問選D是因為當用6-cylinder engine時, trailer hitch不一定要用嗎?
謝謝解說哦~

[Ivy-Canada]

我的算法是:
6-cylinder engine or a 4-cylinder engine & a manual transmission or an automatic transmission-->這邊有4個combination

6-cylinder engine又可分為 trailer hitch+ manual 跟trailer hitch + automatic-->所以又有2個combination

總共有: 4+2=6個combination

不知道這樣算對不對~~請指教..