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

It is currently 19 Jan 2019, 13:13

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
Events & Promotions in January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
  • FREE Quant Workshop by e-GMAT!

     January 20, 2019

     January 20, 2019

     07:00 AM PST

     07:00 AM PST

    Get personalized insights on how to achieve your Target Quant Score.
  • Free GMAT Strategy Webinar

     January 19, 2019

     January 19, 2019

     07:00 AM PST

     09:00 AM PST

    Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.

If x is even, which of the following could be odd ?

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

Hide Tags

 
Board of Directors
User avatar
P
Joined: 01 Sep 2010
Posts: 3280
If x is even, which of the following could be odd ?  [#permalink]

Show Tags

New post 04 Apr 2018, 15:25
Top Contributor
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

70% (01:39) correct 30% (01:25) wrong based on 60 sessions

HideShow timer Statistics

If x is even, which of the following could be odd ?

A. \(\frac{(x^2 + x)(x + 2)}{4}\)

B. \(x^3 - 3x^2 + 2x\)

C. \(x^2 - 4x + 6\)

D. \(\frac{x^3 + x^2}{4}\)

E. \(\frac{(x - 2)(x^2 + 2x)}{4}\)

Kudos for the right answer and explanation

_________________

COLLECTION OF QUESTIONS AND RESOURCES
Quant: 1. ALL GMATPrep questions Quant/Verbal 2. Bunuel Signature Collection - The Next Generation 3. Bunuel Signature Collection ALL-IN-ONE WITH SOLUTIONS 4. Veritas Prep Blog PDF Version 5. MGMAT Study Hall Thursdays with Ron Quant Videos
Verbal:1. Verbal question bank and directories by Carcass 2. MGMAT Study Hall Thursdays with Ron Verbal Videos 3. Critical Reasoning_Oldy but goldy question banks 4. Sentence Correction_Oldy but goldy question banks 5. Reading-comprehension_Oldy but goldy question banks

Manager
Manager
avatar
G
Joined: 30 Mar 2017
Posts: 134
GMAT 1: 200 Q1 V1
Reviews Badge
Re: If x is even, which of the following could be odd ?  [#permalink]

Show Tags

New post 04 Apr 2018, 16:36
1
Answer choice B and C will always be even, so can eliminate those. The numerator of choice A, D, and E will always be even, but when divided by 4, may give an odd number. What is one example of an even number that, when divided by 4, will result in an odd number? 12. Choice D immediately sticks out because 2^3=8 and 2^2=4.

Answer: D

For a more systematic approach, can do this...

Since we've narrowed down the answers to A, D, or E, and all 3 have 4 in the denominator, that means the numerator must be of the form 4*odd so that the 4 in the numerator and the 4 in the denominator cancel out and we're left with the odd number.

Let's examine each numerator.

Choice A
\((x^2+x)(x+2)=x(x+1)(x+2)\)
If x=2, the even factors wont cancel out. x=0 wont work and picking other even values for x will just introduce more even factors. So this can't be odd.

Choice D
\(x^3+x^2=x^2(x+1)\)
If x=2, then the even factors cancel out and we're left with an odd number.

Choice E
\((x-2)(x^2+2x)=x(x-2)(x+2)\)
All factors are even.
GMAT Club Bot
Re: If x is even, which of the following could be odd ? &nbs [#permalink] 04 Apr 2018, 16:36
Display posts from previous: Sort by

If x is even, which of the following could be odd ?

  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®.