Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 12 Feb 2016, 21:57

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# What is (1/16)^(-1/4) (m25#11)

 Question banks Downloads My Bookmarks Reviews Important topics
Author Message
CIO
Joined: 02 Oct 2007
Posts: 1218
Followers: 94

Kudos [?]: 826 [0], given: 334

What is (1/16)^(-1/4) (m25#11) [#permalink]  15 Feb 2012, 05:45
What is $$(\frac{1}{16})^{-\frac{1}{4}}$$ ?

(A) $$-\frac{1}{2}$$
(B) $$2$$
(C) $$256^2$$
(D) $$\frac{1}{2}$$
(E) $$4$$
_________________

Welcome to GMAT Club!

Want to solve GMAT questions on the go? GMAT Club iPhone app will help.
Please read this before posting in GMAT Club Tests forum
Result correlation between real GMAT and GMAT Club Tests
Are GMAT Club Test sets ordered in any way?

Take 15 free tests with questions from GMAT Club, Knewton, Manhattan GMAT, and Veritas.

GMAT Club Premium Membership - big benefits and savings

Magoosh GMAT Instructor
Joined: 28 Dec 2011
Posts: 2791
Followers: 947

Kudos [?]: 3974 [5] , given: 44

Re: What is (1/16)^(-1/4) (m25#11) [#permalink]  17 Feb 2012, 11:26
5
This post received
KUDOS
Expert's post
Hi, there! I'm happy to help with this.

What is (1/16)^(-1/4)
(A) -1/2
(B) 2
(C) 256^2
(D) 1/2
(E) 4

Well, this one combines a few good exponent rules.

First of all:

(any positive number)^(any power at all) = a positive number

so, right away, answer (A) is out.

One BIG idea --- a negative exponent means: take the reciprocal.

a^(-n) = 1/(a^n)

(1/a)^(-n) = a^n

Thus, (1/16)^(-1/4) = 16^(1/4)

Another BIG idea --- a fractional exponent means take a root.

a^(1/2) = the square root of a
a^(1/3) = the cube root of a
a^(1/4) = the fourth root of a

So, 16^(1/4) equals the fourth root of 16. What number, when raised to the fourth power, equals 16? That number is 2, because 2^4 = 2x2x2x2 = 16.

[Reveal] Spoiler:
Thus, Answer = B

Here's a challenging practice PS on laws of exponents

http://gmat.magoosh.com/questions/725

The question at that link should be followed by a complete video solution when you submit your answer.

Does all this make sense? Please let me know if you have any questions.

Mike
_________________

Mike McGarry
Magoosh Test Prep

Re: What is (1/16)^(-1/4) (m25#11)   [#permalink] 17 Feb 2012, 11:26
Similar topics Replies Last post
Similar
Topics:
1 If Z is an integer, what is the value of Z ? 3 26 Dec 2012, 19:45
1 What is the units digit of the above expression? 1 18 Nov 2012, 03:02
1 What is the area of rectangle ABCD? 1 12 Sep 2012, 17:15
What do the scores mean and what does "weight" mean 1 03 Jul 2012, 09:08
What is my current level ? 2 24 Nov 2011, 23:44
Display posts from previous: Sort by

# What is (1/16)^(-1/4) (m25#11)

 Question banks Downloads My Bookmarks Reviews Important topics

Moderators: Bunuel, WoundedTiger

 Powered by phpBB © phpBB Group and phpBB SEO Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.