推 Vinicks:either A or B or C意思是說 是A 是B 也是 C... 10/25 01:03
→ Vinicks:不用寫這麼繞口.簡單來說就是W是odd, X是odd, W.X也是oodd 10/25 01:04
→ moli1984:那為啥(A)不充分啊~@@~ 10/25 21:41
195. 18858-!-item-!-187;#058&012264
If w, x, y, and z are integers such that w/x and y/z are integers
, is w/x + y/z odd?
(1) wx + yz is odd.
(2) wz + xy is odd.
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答案是B
但我不能理解A選項的理由:
suppose wx is odd, either w or x or both could be odd. If w and x are both
odd, w/x is odd. If w is even and x is odd, w/x is even.
如果wx是奇數 那 w & x不是都應為奇數嗎?
謝謝各位板友~
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