这道Prep数学题，看不懂题目，求教高手

theresalwaysme

DS: If  500 is the multiple of 100 that is closest to x and 400 is the multiple of 100 that is cloest to y, which mutiple of 100 is closest to x+y?

(1) x<500
(2) y<400

题目现在都还没看明白，模考的时候直接放弃了。 请高手看看。

pfullsomer

multiple of 100: 100, 200, 300, 400, 500, 600, . . .

Among the above candidates, 500 is the closest to x and 400 is the closest to y. Do you know which of the above numbers is closest to x+y?

Premise:  450<x<550 and 350<y<450

condition 1) 450<x<500, 800<x+y<950.  The multiple of 100 could be 800, 900,
condition 2) 350<y<400, 800<x+y<950.  The multiple of 100 could be 800, 900
conditions 1) and 2) 450<x<500, 350<y<400, 800<x+y<900. The multiple of 100 could be 800, 900.


E

theresalwaysme

基本明白了，

感觉原文中的 500 is the multiple of 100，这不是废话吗？500是100的倍数， 400是100的倍数，谁都知道。题目要是你么解释一下，其实蛮简单的。