BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Data Sufficiency from GMAT Prep - Logic to approach needed

Expert replies
Source: — Data Sufficiency |

by neelgandham » Mon Nov 14, 2011 12:39 pm
Hi Amit,

This question has already been answered. Please find below the urls

https://www.beatthegmat.com/gmatprep-is- ... 23339.html
https://www.beatthegmat.com/gmat-prep-qu ... 17223.html
Anil Gandham
Welcome to BEATtheGMAT | Photography | Getting Started | BTG Community rules | MBA Watch
Check out GMAT Prep Now's online course at https://www.gmatprepnow.com/
Join the discussion

by GMATGuruNY » Mon Nov 14, 2011 5:26 pm
Is x^4 + y^4 > z^4?

Statement 1: x² + y² > z²
Statement 2: x+y > z.
Try to plug in combinations that satisfy both statements.
An easy value to raise to the 4th power is a root.
√2 ≈ 1.4.
√3 ≈ 1.7.

Let x=1, y=1 and z=1.
Statement 1:
1² + 1² > 1².
2 > 1.
Satisfied.

Statement 2:
1+1 > 1.
2 > 1.
Satisfied.

Question stem:
1^4 + 1^4 > 1^4.
2 > 1.
YES.

Let x=√2, y=√3 and z=√4=2.
Statement 1:
√2² + √3² > 2².
5 > 4.
Satisfied.

Statement 2:
√2+√3 > 2.
3.1 > 2.
Satisfied.

Question stem:
(√2)^4 + (√3)^4 > 2^4.
13 > 16.
NO.

Since the combinations above satisfy both statements, and in the first case the answer is YES, and in the second case the answer is NO, INSUFFICIENT.

The correct answer is E.
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
Join the discussion