It is currently 19 Sep 2019, 00:16
My Tests

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.

A function f(x) is defined for all real numbers as f(x) = (x

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Founder
Founder
User avatar
Joined: 18 Apr 2015
Posts: 8120
Followers: 157

Kudos [?]: 1700 [0], given: 7473

CAT Tests
A function f(x) is defined for all real numbers as f(x) = (x [#permalink] New post 14 May 2019, 01:10
Expert's post
00:00

Question Stats:

89% (00:25) correct 10% (00:00) wrong based on 19 sessions
A function f(x) is defined for all real numbers as f(x) = (x – 1)(x – 2)(x – 3)(x – 4)


Quantity A
Quantity B
f(2.5)
f(3.5)


A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
[Reveal] Spoiler: OA

_________________

Get the 2 FREE GREPrepclub Tests

3 KUDOS received
MyGuru Representative
User avatar
Affiliations: Partner at MyGuru LLC.
Joined: 13 May 2019
Posts: 130
Location: United States
GMAT 1: 770 Q51 V44
GRE 1: Q169 V168
WE: Education (Education)
Followers: 3

Kudos [?]: 125 [3] , given: 2

CAT Tests
Re: A function f(x) is defined for all real numbers as f(x) = (x [#permalink] New post 14 May 2019, 13:45
3
This post received
KUDOS
Expert's post
With GRE Quantitative Comparisons look for savvy methods for comparison to avoid unnecessary calculation. In this case note the number of negative values created in each quantity.

Quote:
A function f(x) is defined for all real numbers as f(x) = (x – 1)(x – 2)(x – 3)(x – 4)

Quantity A
Quantity B
f(2.5)
f(3.5)


Now for Quantity A: x - 1 and x - 2 are each > 0 | x - 3 and x - 4 are each < 0 --> Positive x Positive x Negative x Negative will result in a product > 0
Now for Quantity B: x - 1 is the only value > 0 --> Positive x Negative x Negative x Negative will result in a product < 0

Therefore, Quantity A will always be greater and the correct choice is A.
_________________

Stefan Maisnier


Director of Online Tutoring, MyGuru
www.myguruedge.com



Sign up today for a free 30-minute online GRE tutoring session!


Like us on Facebook
Watch us on YouTube
Follow us on Twitter
Follow us on Linkedin

Manager
Manager
Joined: 22 May 2019
Posts: 58
Followers: 0

Kudos [?]: 22 [0], given: 194

Re: A function f(x) is defined for all real numbers as f(x) = (x [#permalink] New post 27 Jul 2019, 13:36
MyGuruStefan wrote:
With GRE Quantitative Comparisons look for savvy methods for comparison to avoid unnecessary calculation. In this case note the number of negative values created in each quantity.

Quote:
A function f(x) is defined for all real numbers as f(x) = (x – 1)(x – 2)(x – 3)(x – 4)

Quantity A
Quantity B
f(2.5)
f(3.5)


Now for Quantity A: x - 1 and x - 2 are each > 0 | x - 3 and x - 4 are each < 0 --> Positive x Positive x Negative x Negative will result in a product > 0
Now for Quantity B: x - 1 is the only value > 0 --> Positive x Negative x Negative x Negative will result in a product < 0

Therefore, Quantity A will always be greater and the correct choice is A.

In quantity B, x-1, x-2 and x-3 all are positive, only x-4 is negative.
2 KUDOS received
GRE Instructor
User avatar
Joined: 10 Apr 2015
Posts: 2386
Followers: 77

Kudos [?]: 2353 [2] , given: 33

CAT Tests
Re: A function f(x) is defined for all real numbers as f(x) = (x [#permalink] New post 03 Aug 2019, 06:29
2
This post received
KUDOS
Expert's post
Carcass wrote:
A function f(x) is defined for all real numbers as f(x) = (x – 1)(x – 2)(x – 3)(x – 4)


Quantity A
Quantity B
f(2.5)
f(3.5)


A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.


Quantity A: f(2.5) = (2.5 – 1)(2.5 – 2)(2.5 – 3)(2.5 – 4)
= (1.5)(0.5)(-0.5)(-1.5)
= (POSITIVE)(POSITIVE)(NEGATIVE)(NEGATIVE)
= (POSITIVE)(POSITIVE)(POSITIVE)
= POSITIVE

Quantity B: f(3.5) = (3.5 – 1)(3.5 – 2)(3.5 – 3)(3.5 – 4)
= (2.5)(1.5)(0.5)(-0.5)
= (POSITIVE)(POSITIVE)(POSITIVE)(NEGATIVE)
= (POSITIVE)(NEGATIVE)
= NEGATIVE

Answer: A

Cheers,
Brent
_________________

Brent Hanneson – Creator of greenlighttestprep.com
Image
Sign up for my free GRE Question of the Day emails

Re: A function f(x) is defined for all real numbers as f(x) = (x   [#permalink] 03 Aug 2019, 06:29
Display posts from previous: Sort by

A function f(x) is defined for all real numbers as f(x) = (x

  Question banks Downloads My Bookmarks Reviews Important topics  


GRE Prep Club Forum Home| About| Terms and Conditions and Privacy Policy| GRE Prep Club Rules| Contact

Powered by phpBB © phpBB Group

Kindly note that the GRE® test is a registered trademark of the Educational Testing Service®, and this site has neither been reviewed nor endorsed by ETS®.