Bunuel wrote:
If x is a positive integer greater than 1, what is the value of x?
(1) 2x is a common factor of 18 and 24
(2) x is a factor of 6
Target question: What is the value of x? Given: x is a positive integer greater than 1 Statement 1: 2x is a common factor of 18 and 24 Positive factors of 18: 1, 2, 3, 6, 9, 18
Positive factors of 24: 1, 2, 3, 4, 6, 8, 12, 24
COMMON factors of 18 and 24: 1, 2, 3, 6
So, 2x = 1, 2x = 2, 2x = 3 or 2x = 6
This means, x = 0.5, x = 1, x = 1.5 or x = 3
Since we're told that x is a positive integer greater than 1, we can see that
x MUST equal 3Since we can answer the
target question with certainty, statement 1 is SUFFICIENT
Statement 2: x is a factor of 6 So, x could equal 1, 2, 3, or 6
Since we're told that x is a positive integer greater than 1, we can see that
x COULD equal 2, 3, or 6Since we cannot answer the
target question with certainty, statement 2 is NOT SUFFICIENT
Answer: A
RELATED VIDEO
_________________
Brent Hanneson – Creator of gmatprepnow.com
Before you spend another second preparing for the GMAT, check out my article series, Are you doing it wrong?.
You’ll learn what the GMAT actually tests, and why memorizing a ton of formulas actually makes you less effective.