BTGModeratorVI wrote: ↑Thu Aug 20, 2020 7:20 am
Is x-y+1 greater than x+y-1 ?
(1) x > 0
(2) y < 0
Answer:
B
Source: GMAT prep
Target question: Is x - y + 1 > x + y - 1 ?
This is a good candidate for
rephrasing the target question.
Take:
x - y + 1 > x + y - 1
Subtract x from both sides to get:
-y + 1 > y - 1
Add y to both sides to get:
1 > 2y - 1
Add 1 to both sides to get:
2 > 2y
Divide both sides by 2 to get:
1 > y
REPHRASED target question: Is y < 1?
The video below has tips on rephrasing the target question
Statement 1: x > 0
Since we have no information about y, we cannot answer the
REPHRASED target question with certainty
Statement 1 is NOT SUFFICIENT
Statement 2: y < 0
In other words, y is NEGATIVE
If is NEGATIVE, then
y is definitely less than 1
So, the answer to the REPHRASED target question is
YES, y IS less than 1
Since we cannot answer the
target question with certainty, statement 2 is NOT SUFFICIENT
Answer: B
Cheers,
Brent
