If |x – y| = 5, what is the value of x?

This topic has expert replies
Source: — Data Sufficiency |

GMAT/MBA Expert

User avatar
Elite Legendary Member
Posts: 10392
Joined: Sun Jun 23, 2013 6:38 pm
Location: Palo Alto, CA
Thanked: 2867 times
Followed by:511 members
GMAT Score:800

by [email protected] » Sat Mar 31, 2018 12:01 pm
Hi M7MBA,

We're told that |X - Y| = 5. We're asked for the value of X. This question can be solved with a bit of Arithmetic and TESTing VALUES.

1) Y = 5

With the information in Fact 1, we have the equation |X - 5| = 5. This equation has TWO solutions: 10 and 0
|10 - 5| = 5
|0 - 5| = |-5| = 5
Fact 1 is INSUFFICIENT

2) X > 0

With Fact 2, we know that X is POSITIVE, but that does not limit the number of possible solutions (since Y can be anything).
Fact 2 is INSUFFICIENT

Combined, we know...
Y = 5 and X = 10 or 0
X > 0

The ONLY solution that 'fits' both Facts is X=10

Final Answer: C

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
Image