GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 22 Oct 2018, 03:00

Close

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

For all positive integers, x, f(x) = 3x when x is an odd integer and f

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 50039
For all positive integers, x, f(x) = 3x when x is an odd integer and f  [#permalink]

Show Tags

New post 03 Jan 2017, 02:33
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

71% (01:23) correct 29% (01:26) wrong based on 118 sessions

HideShow timer Statistics

For all positive integers, x, f(x) = 3x when x is an odd integer and f(x) = 1/4*x when x is even. Which of the following is equivalent to f(24) + f(9)?

A. f(99)
B. f(11)
C. f(33)
D. f(54)
E. f(72)

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

VP
VP
User avatar
P
Joined: 05 Mar 2015
Posts: 1000
Re: For all positive integers, x, f(x) = 3x when x is an odd integer and f  [#permalink]

Show Tags

New post 03 Jan 2017, 09:39
1
Bunuel wrote:
For all positive integers, x, f(x) = 3x when x is an odd integer and f(x) = 1/4*x when x is even. Which of the following is equivalent to f(24) + f(9)?

A. f(99)
B. f(11)
C. f(33)
D. f(54)
E. f(72)


f(9)= 3*9=27
f(24)=24/4=6
thus f(24) + f(9)=33
or 3*11====3*x(11)=f(11)

Ans B
Target Test Prep Representative
User avatar
P
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 3907
Location: United States (CA)
Re: For all positive integers, x, f(x) = 3x when x is an odd integer and f  [#permalink]

Show Tags

New post 04 Jan 2017, 08:30
1
Bunuel wrote:
For all positive integers, x, f(x) = 3x when x is an odd integer and f(x) = 1/4*x when x is even. Which of the following is equivalent to f(24) + f(9)?

A. f(99)
B. f(11)
C. f(33)
D. f(54)
E. f(72)


We are given that f(x) = 3x when x is an odd integer, and f(x) = 1/4*x when x is even. We need to determine what is equivalent to f(24) + f(9).

Since 24 is even, f(24) = (1/4) x 24 = 6.

Since 9 is odd, f(9) = 3 x 9 = 27.

Thus, f(24) + f(9) = 6 + 27 = 33.

The only answer choice that is equivalent to 33, is f(11):

Since 11 is odd, f(11) = 11 x 3 = 33.

Answer: B
_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Director
Director
avatar
S
Joined: 12 Nov 2016
Posts: 749
Location: United States
Schools: Yale '18
GMAT 1: 650 Q43 V37
GRE 1: Q157 V158
GPA: 2.66
Re: For all positive integers, x, f(x) = 3x when x is an odd integer and f  [#permalink]

Show Tags

New post 20 Feb 2017, 19:44
1
For all positive integers, x, f(x) = 3x when x is an odd integer and f(x) = 1/4*x when x is even. Which of the following is equivalent to f(24) + f(9)?

Okay so learned my mistake from a similar problem:

https://gmatclub.com/forum/for-all-posi ... 25937.html

F(x)= 3X when 1,3,5.... (trying to transition from a poet to quant by thinking outloud in numbers, like the guy in a beautiful mind, instead of thinking ok odd so which F( ) falls under this category- faster because sometime they'll list the criteria as f when odd and f when even then give you even + odd in order to confuse you smh the old switcharoo)
F(x)=1/4*x when 2,4,6...

F(9)= 3(9)
=27

F(24)= 1/4 (24) (thank God playing challenge 24 as a kid and always getting owned by my friend eventually saturated the properties of 24 in me)
=6

27 +6 = 33 BUT wait this does not mean F(33)! Remember what F(33) actually represents, according the question, is F(33)=3 (33)= 99
Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 8515
Premium Member
Re: For all positive integers, x, f(x) = 3x when x is an odd integer and f  [#permalink]

Show Tags

New post 21 Sep 2018, 08:56
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

GMAT Club Bot
Re: For all positive integers, x, f(x) = 3x when x is an odd integer and f &nbs [#permalink] 21 Sep 2018, 08:56
Display posts from previous: Sort by

For all positive integers, x, f(x) = 3x when x is an odd integer and f

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.