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

It is currently 16 Aug 2018, 10:58
Register
GMAT Club Tests
Decision Tracker
My Rewards
New posts
Unanswered

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.

Go to My Error Log Learn more
Close

Request Expert Reply

Confirm Cancel

M03-22

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
  Sort by Date Sort by Kudos  
Search for:
 
First unread post
Author Message
TAGS:

Hide Tags
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47945
Premium Member CAT Tests
Top Member of the Month
M03-22  [#permalink]

Show Tags

New post 16 Sep 2014, 00:20
1
1
4
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

62% (01:05) correct 38% (01:00) wrong based on 227 sessions

HideShow timer Statistics

Is the product of three integers \(p\), \(q\), and \(r\) even?


(1) \((p - 1)(r + 1)\) is odd

(2) \((q - r)^2\) is odd
Spoiler: OA

_________________

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

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47945
Premium Member CAT Tests
Top Member of the Month
Re M03-22  [#permalink]

Show Tags

New post 16 Sep 2014, 00:20
2
Official Solution:


For a product of 3 integers to be even, at least one integer must be even. For example \(1 * 3 * 5 = 15\), odd vs. \(5 * 7 * 2 = 70\), even.

Statement (1) by itself is sufficient. For \((p - 1)(r + 1)\) to be odd, both \(p - 1\) and \(r + 1\) must be odd. Therefore, both \(p\) and \(r\) are even.

Statement (2) by itself is sufficient. The product of two integers is odd only if both integers are odd, therefore the result of \(q - r\) is odd. For a difference of two integers to be odd, one of the two must be even. One even integer is sufficient to make the product \(pqr\) even.


Answer: D
_________________

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

Intern
Intern
avatar
Joined: 09 Aug 2014
Posts: 3
Location: United States
Concentration: Other
GMAT 1: 680 Q42 V41
GPA: 3.44
WE: Education (Education)
Re: M03-22  [#permalink]

Show Tags

New post 29 Dec 2014, 02:25
Bunuel But what about if q is 0 for the first one or if q or r is 0 for the second one?
Intern
Intern
avatar
Joined: 24 Jan 2015
Posts: 2
Re: M03-22  [#permalink]

Show Tags

New post 29 May 2015, 05:08
zero is even number
SC Moderator
User avatar
D
Joined: 13 Apr 2015
Posts: 1711
Location: India
Concentration: Strategy, General Management
Schools: Stern '21, HEC Sept19 intake, Rotman '21
GMAT 1: 200 Q1 V1
GPA: 4
WE: Analyst (Retail)
GMAT ToolKit User Premium Member CAT Tests
Re: M03-22  [#permalink]

Show Tags

New post 29 May 2015, 07:02
Statement 1: (p-1)(r+1) = (pr+p-r-1). This will be odd only (pr+p-r) is even. (pr+p-r) is even only when p and r are even. Since p and r are even. Product of p, q and r is always even. (Sufficient)

Statement 2: (q-r)^2 is odd when (q-r) is odd. (q-r) will be odd when either q or r is even and the other one is odd. Since q or r is even, product of p, q and r will always be even. (Sufficient)

Answer: D
Current Student
avatar
Joined: 18 Aug 2015
Posts: 5
Location: India
Schools: McCombs '19 (A)
GMAT 1: 730 Q50 V39
GPA: 3.2
Reviews Badge
Re M03-22  [#permalink]

Show Tags

New post 23 Oct 2015, 11:46
I think this is a high-quality question and I don't agree with the explanation. For option 2, is it not possible that q is odd and r is 0, which makes (q-r) * (q-r) as odd and hence the statement is not sufficient because it will depend on the value of P.

Please clarify
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47945
Premium Member CAT Tests
Top Member of the Month
Re: M03-22  [#permalink]

Show Tags

New post 24 Oct 2015, 02:28
mohitmaheshwari20 wrote:
I think this is a high-quality question and I don't agree with the explanation. For option 2, is it not possible that q is odd and r is 0, which makes (q-r) * (q-r) as odd and hence the statement is not sufficient because it will depend on the value of P.

Please clarify



You should brush-up fundamentals before attempting questions: 0 is an even integer.
_________________

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

Intern
Intern
avatar
Joined: 02 Feb 2016
Posts: 2
Re M03-22  [#permalink]

Show Tags

New post 24 Feb 2016, 19:01
I think this is a poor-quality question and I don't agree with the explanation. No you don't know if Q is 0 or not for 1) or if P is 0 in 2)
Math Expert
User avatar
V
Joined: 02 Aug 2009
Posts: 6533
Premium Member Reviews Badge
Top Member of the Month
Re: M03-22  [#permalink]

Show Tags

New post 24 Feb 2016, 19:45
Binglai wrote:
I think this is a poor-quality question and I don't agree with the explanation. No you don't know if Q is 0 or not for 1) or if P is 0 in 2)


Hi,
the Q is perfectly fine..
you will have to brush up a bit of basics on number, since 0 is an even number and is neither positive or negative..
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html


GMAT online Tutor

Intern
Intern
avatar
Joined: 09 May 2016
Posts: 1
Re M03-22  [#permalink]

Show Tags

New post 11 May 2016, 16:55
I think this is a poor-quality question and I don't agree with the explanation. What if one of p, r, q was zero?
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47945
Premium Member CAT Tests
Top Member of the Month
Re: M03-22  [#permalink]

Show Tags

New post 11 May 2016, 17:24
mengsy wrote:
I think this is a poor-quality question and I don't agree with the explanation. What if one of p, r, q was zero?


You should brush-up fundamentals before attempting questions: 0 is an even integer.
_________________

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

Manager
Manager
User avatar
B
Joined: 23 Jun 2009
Posts: 196
Location: Brazil
GMAT 1: 470 Q30 V20
GMAT 2: 620 Q42 V33
GMAT ToolKit User Premium Member
M03-22  [#permalink]

Show Tags

New post 03 Aug 2016, 07:26
Bunuel wrote:
mengsy wrote:
I think this is a poor-quality question and I don't agree with the explanation. What if one of p, r, q was zero?


You should brush-up fundamentals before attempting questions: 0 is an even integer.


I think we must keep our politeness whenever possible. The questions are repeated over and over. The simple fact of not getting it right worth analyzing it and putting it in you error log. Next time this mistake won't happen. 8-)
>> !!!

You do not have the required permissions to view the files attached to this post.

Intern
Intern
avatar
B
Joined: 21 May 2015
Posts: 17
GMAT ToolKit User
Re M03-22  [#permalink]

Show Tags

New post 22 Aug 2017, 16:01
I think this is a high-quality question and I agree with explanation.
Re M03-22 &nbs [#permalink] 22 Aug 2017, 16:01
Print view
First unread post
Display posts from previous: Sort by

M03-22

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

Moderators: chetan2u, Bunuel

Search for:

Events & Promotions

PREV
NEXT


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®.

Main navigation

GMAT Resources

Partners

MBA Resources

www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions