If 500 is the multiple of 100 that is closest to X and 400 is the multiple of 100 that is closest to Y 从这句话,我们知道 550<x<450 , 450<y<350, 1000<x+y<800 单独(1) X 小于500 550<x<500 1000<x+y<850 无法判断which multiple of 100 is closest to X +Y 同理,单独(2)也不行 1)2) 550<x<500 , 450<y<400 1000<x+y<900 所以 还是无法判断 选E |