A和B 都是整数 A-B和A/B都是偶数 问一下哪一个一定是奇数？ A。A/2 B。B/2 C。(A+B)/2 D. (A+2)/2 E。(B+2)/2 the answer given is D. However, because A and B should be odd or even simutaneously, I think if D is correct, Eshould also be correct!!! I doubt the answer given. I think the answer should be C. What do you guys think?
If A/B is even, it proves that A is even, A = 2*a*B and A>B. Then since A and B are both even or both odd, then B is even as well, so A =2*a*2*b = 4*a*b.
Then (A+2)/2 = 2*a*b + 1 = odd.
Only D must be right.
For E, if B=2 or B=4, you get different answers.
For C, if A=4, B=2; or A=4, B=4; you get different answers.
京公网安备11010202008513号 京ICP证101109号 京ICP备12012021号
发表于 2011-6-27 09:30:36
收藏
收藏
楼主
