Did this question very literally.
If 500 is the multiple of 100 that is closest to X and 400 is the multiple of 100 closest to Y, then which multiple of 100 closest to X + Y?
(1) X < 500
Say X is 499 --> and Y is 399--> X+Y = 898.
if Y is 400 then 499 +400 = 899
but if Y is 300 (multiple of 100, is closest to 300) --> 499+ 300 = 799.
Not suff
(2) Y < 400
Y = 399 and X is 400. x + y = 799. if Y =399 + 499 =898 if we take different cases we get different values which are multiples of 100
1) 2) getting more than 1 multiple of 100. So E.
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