Is x > y?

This topic has expert replies
Senior | Next Rank: 100 Posts
Posts: 73
Joined: Fri Jul 23, 2010 1:30 pm

Is x > y?

by PGMAT » Sat Apr 07, 2012 2:45 pm
Is x > y?

(1) √x > y

(2) x^3 > y

Can some one please explain?

OA C

User avatar
GMAT Instructor
Posts: 1248
Joined: Thu Mar 29, 2012 2:57 pm
Location: Everywhere
Thanked: 503 times
Followed by:192 members
GMAT Score:780

by Bill@VeritasPrep » Sat Apr 07, 2012 3:15 pm
1) If x=4 and y =1, then sqrt(x) = 2 and x > y. However, if x = 1/4 and y = 1/3, then sqrt(x) = 1/2 and x < y. Insufficient.

2) If x=4 and y=1, then x^3 = 64 and x > y. However, if x=4 and y=6, x^3 is still greater than y, but x < y. Insufficient.

Combined, Statement 2 rules out the fraction possibility from Statement 1, and Statement 1 rules out the second example from Statement 2. If the square root of x and x^3 are both greater than y, then x itself must also be greater than Y. Sufficient.
Join Veritas Prep's 2010 Instructor of the Year, Matt Douglas for GMATT Mondays

Visit the Veritas Prep Blog

Try the FREE Veritas Prep Practice Test

User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pm
Location: New York, NY
Thanked: 13060 times
Followed by:1906 members
GMAT Score:790

by GMATGuruNY » Sat Apr 07, 2012 5:06 pm
For two alternate approaches, check here:

https://www.beatthegmat.com/ds-inequalit ... 02609.html
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