Is x less than y?

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Re: Is x less than y?

by Brent@GMATPrepNow » Wed Feb 26, 2020 5:24 pm

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BTGModeratorVI wrote: ↑
Wed Feb 26, 2020 4:20 pm
Is x less than y?

(1) x - y + 1 < 0
(2) x - y - 1 < 0

Answer: A
Source: Official Guide

Target question: Is x < y?

Statement 1: x-y+1<0
Add y to both sides to get x+1 < y
Since x < x + 1, we can write: x < x+1 < y
From this, we can definitely see that x < y
So, statement 1 is SUFFICIENT

Statement 2: x - y - 1 < 0
Add y to both sides to get x - 1 < y
Since x - 1 < x,
We can see that y and x are both greater than x - 1, but we can't tell whether x < y
So, statement 2 is NOT SUFFICIENT

Answer: A

Cheers,
Brent

Brent Hanneson - Creator of GMATPrepNow.com