请教FF-7-17

mingzhu11

17、If x and y both positive numbers,is at least one of them even?
(1)x+y is odd (2)x-y is odd

如果X,Y都是分数，那么答案是不是不对了？POSITIVE NUMBERS BUT NOT POSITIVE INTEGERS.

mingzhu11

sorry ,i make a concept fallacy,if x,y are positive,so the answer is e,right?blackhorse.

i always confuse about the category of the numbers,could you tell me a lot?

huahua115

blackhorse肯定么？我觉得number不是整数，因为有non-integral number一说。这题的表达有问题，本意应该是指整数的。

falcons

答案选D。不过你这么一问，我倒是从没有想过number会不是整数。我想如果是小数或者分数，应该叫fraction或者decimal吧。再查查。