gmatbull wrote:
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
(2) Y < 400
Above is a GMATPREP2 question. One solution says:
"since the numbers don't have to be integers, you have
1. 450 < x < 550 (excluding BOTH endpoints) - note that x could be 450.00001 or 549.99999
2. 350 < y < 450 (again excluding both endpoints)..."
If x < 500 and 500 is the multiple of 100 closest to it, i think the condition
450 <= x < 550 would suffice - after all, 450 to the nearest 100 = 500?
Same issue applicable to 350 < y < 450 should be 350 <= y < 450
Kindly respond please. (N.B: I've tried a search on the topic but the response returned 2081 results!!)
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
(2) Y < 400
Question :
450<X<550 and 350<Y<450
?<X+Y<?
(1) X < 500
Now,
450<X<500 and 350<Y<450
Higher range => 490+440 = 930 (No closest: 900)
Lower range => 460+360 = 820 (No closest: 800)
Not sufficient
(2) Y < 400
Now,
450<X<550 and 350<Y<400
Higher range =>540+390 = 930 (No closest: 900)
Lower range =>460+360 = 820 (No closest: 800 )
Not sufficient
(1) + (2) combined.
Now,
450<X<500 and 350<Y<400
Higher range =>490+390 = 880 (No closest: 900)
Lower range =>460+360 = 820 (No closest: 800 )
Not sufficient
Ans: E