• Board contributors include instructors with "800" GMAT scores.
  • 95% of posts have replies within 24 hours.
  • Join for discounts with 800score, VeritasPrep and ManhattanGMAT


FAQ  - Register  - Search - Login 

All times are UTC - 7 hours




Post new topic Reply to topic  [ 2 posts ] 
Author Message
 Post subject: GMAT Symbols
PostPosted: Wed Apr 10, 2013 9:00 am 
Offline
User avatar

Joined: Tue Apr 13, 2010 8:48 am
Posts: 480
If @(n) is defined as the product of the cube root of n and the positive square root of n, then for what number n does @(n) = 50 percent of n?

A. 16
B. 64
C. 100
D. 144
E. 729

(B) On test day, the @ symbol or any other symbol in a question usually represents a function. Though this question could be solved algebraically using fractional exponents, it is probably easiest to Backsolve from the answer choices.

Since choices (A), (C) and (D) don’t have integer cube roots, and because choice (E) is odd (so 50% of it is not an integer), let’s try choice (B) first.

The cube root of 64 is 4 and the positive square root of 64 is 8, so @(64) = 4 × 8 = 32, which is 50% of 64. The answer is (B)

-------------
Can this question be arithmetically solved?


Top
 Profile  
 
 Post subject: Re: GMAT Symbols
PostPosted: Wed Apr 10, 2013 9:01 am 
Offline
User avatar

Joined: Fri Apr 09, 2010 2:11 pm
Posts: 456
If you are not familiar with fractional exponents then you should solve by plugging in answer choices. However if you are then you can solve the given equation algebraically.

@(n) = 50 percent of n
can be rewritten as equation:
Image

Since √n must be positive then n = 64
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC - 7 hours


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
Template made by DEVPPL -
phpBB SEO
 
GMAT(TM) and GMAT CAT (TM) are registered trademarks of the Graduate Management Admission Council(TM). The Graduate Management Admission Council(TM) does not endorse, nor is affiliated in any way with the owner or any content of this site.