一道PREP数学题，没看懂题，希望NN解答

wangshuo_922

500是100的倍数最接近X的，400是100的倍数最接近Y的，那么10的倍数最接近X+Y 是什么?
X可以从451~549吧~Y是351~449，所以X+Y从802~1098 你能确定10的倍数是几么？

If 500 is the multiple of 100 that is closest to X and 400 is the multiple of 100 that is closest to Y ,which multiple of 10 is closest to X+Y
1) X<500
2) Y<400
答案是E，没看懂题，盼NN解答

-- by 会员 拿铁咖啡 (2010/11/1 16:34:59)