M7MBA wrote:If x > 0, is x² < x?
(1) 0.1 < x < 0.4
(2) x^3 < x²
Here's another approach:
Target question: Is x² ＜ x ?
This is a good candidate for
rephrasing the target question.
Aside: Here's a video with tips on rephrasing the target question: https://www.gmatprepnow.com/module/gmat- ... cy?id=1100
Given: x > 0
Since we're told that x is POSITIVE, we can safely take
x² < x and divide both sides by x to get:
x < 1
REPHRASED target question: Is x < 1 ?
Statement 1: 0.1 < x < 0.4
If x is BETWEEN 0.1 and 0.4, then we can be certain that
x < 1
Since we can answer the
REPHRASED target question with certainty, statement 1 is SUFFICIENT
Statement 2: x³ < x²
If x is POSITIVE, then we know that x² is also POSITIVE
This means we can safely take x³ < x² and divide both sides by x² to get
x < 1
Aha! This is exactly what our REPHRASED target question is asking!
Since we can answer the
REPHRASED target question with certainty, statement 2 is SUFFICIENT
Answer: D
Cheers,
Brent
