pp-T1-DS187

[mupeane]

187. 18620-!-item-!-187;#058&011611
If x, y, and z are integers greater than 1, what is the value of x + y + z ?

(1) xyz = 70

(2) x/yz = 7/10

ANS:A

[little8]

(1) xyz=70 =>2x5x7 單獨充分 (要排除掉1x7x10這個可能,因為題目已經說: 正整數的 x, y, and z都>1)
(2)展開後 10x=7yz 無法單獨充分

答案A

[mupeane]

謝謝你喔，我懂了

一開始有點不懂題意