[email protected] wrote:Is x positive?
(1) ( x - 3) 2 > 0
(2) x 3 - 1 > 0
For a question like above, where there is no limitation on x (i.e. x!=0 or x is an integer), would we test for the fringe cases? i.e. test when x is a fraction or when x = 0 etc..
Statement 1: (x-3)² > 0.
It's possible that x=0, since (0-3)² = 9.
It's possible that x=1, since (1-3)² = 4.
Since x is not positive in the first case but x is positive in the second case, INSUFFICIENT.
Statement 2: x³ - 1 > 0
Thus, x³ > 1.
If x<0, then x³<0.
If x=0, then x³=0.
Thus, for it to be true that x³>1, x must be positive.
SUFFICIENT.
The correct answer is
B.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at
[email protected].
Student Review #1
Student Review #2
Student Review #3
