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

It is currently 27 Aug 2016, 22:26
GMAT Club 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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If p, q, and r are integers, is pq + r even?

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

Hide Tags

Senior Manager
Senior Manager
avatar
Joined: 10 Nov 2010
Posts: 267
Location: India
Concentration: Strategy, Operations
GMAT 1: 520 Q42 V19
GMAT 2: 540 Q44 V21
WE: Information Technology (Computer Software)
Followers: 5

Kudos [?]: 238 [0], given: 22

If p, q, and r are integers, is pq + r even? [#permalink]

Show Tags

New post 10 Mar 2011, 13:18
1
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  75% (hard)

Question Stats:

55% (02:57) correct 45% (01:38) wrong based on 112 sessions

HideShow timer Statistics

If p, q, and r are integers, is pq + r even?

(1) p + r is even.
(2) q + r is odd.
[Reveal] Spoiler: OA

_________________

The proof of understanding is the ability to explain it.

1 KUDOS received
Intern
Intern
avatar
Joined: 21 Feb 2013
Posts: 13
Followers: 0

Kudos [?]: 1 [1] , given: 0

If p, q, and r are integers, is pq + r even? [#permalink]

Show Tags

New post 07 Apr 2013, 03:26
1
This post received
KUDOS
If p, q, and r are integers, is pq + r even?

(1) p + r is even.
(2) q + r is odd.

[Reveal] Spoiler:
Manhattan tells me I should make the table which works fine. I tried doing it without the table and that worked too. However, without the table I was less convinced and more confused because in your head it gets jumbled up. So is there another foolproof way of doing these? Or do I have to stick with the Manhattan table?

Last edited by Bunuel on 12 Apr 2013, 05:53, edited 1 time in total.
RENAMED THE TOPIC.
1 KUDOS received
VP
VP
User avatar
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1123
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Followers: 173

Kudos [?]: 1798 [1] , given: 219

GMAT ToolKit User
Re: A proper organised way to solve this type of questions? [#permalink]

Show Tags

New post 07 Apr 2013, 03:46
1
This post received
KUDOS
karmapatell wrote:
If p, q, and r are integers, is pq + r even?

(1) p + r is even.
(2) q + r is odd.

Manhattan tells me I should make the table which works fine. I tried doing it without the table and that worked too. However, without the table I was less convinced and more confused because in your head it gets jumbled up. So is there another foolproof way of doing these? Or do I have to stick with the Manhattan table?


The Manhattan table works fine, another method is using real numbers .

(1) p + r is even. \(3+1 = even\), so is \(3q+1\) even? depends on q : not Sufficient
(2) q + r is odd. \(2+1=odd\), so is \(p2+1\) even? depends on p : not Sufficient

(1)+(2) p + r is even AND q + r is odd
Example 1: \(3+1=even\)--\(2+1 = odd\)
\(2*3+1=odd\)
Example 2:\(2+2=even\)--\(3+2=odd\)
\(2*3+2=even\)
Not Sufficient
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

Manager
Manager
avatar
Joined: 14 Feb 2011
Posts: 196
Followers: 4

Kudos [?]: 110 [0], given: 3

Re: If p, q, and r are integers, is pq + r even? [#permalink]

Show Tags

New post 10 Mar 2011, 13:52
GMATD11 wrote:
1) If p,q and r are integers, is pq+r even?

1) p+r is even
2) q+r is add

M getting D

OA is different. Pls confirm if answer is not D


We want to know if pq+r is even

Statement 1) says p+r is even implying that p and r are either both odd or both even. When they are both even, then irrespective of q being even or odd, pq+r will be even. When they are both odd, depending on q, pq+r can be odd or even. So, insufficient

Statement 2) says q+r is odd, implying at least one of q or r is odd and the other one is even. When r is odd and q is even, pq+r is odd. When q is odd and r is even, pq+r is even or odd depending on value of p, so insufficient.

Combining the two, when p and r are even and hence q is odd, pq+r is even

when p and r are odd and hence q is even, pq+r is odd, so again insufficient

Answer E
Director
Director
avatar
Status: Impossible is not a fact. It's an opinion. It's a dare. Impossible is nothing.
Affiliations: University of Chicago Booth School of Business
Joined: 03 Feb 2011
Posts: 920
Followers: 13

Kudos [?]: 315 [0], given: 123

Reviews Badge
Re: If p, q, and r are integers, is pq + r even? [#permalink]

Show Tags

New post 10 Mar 2011, 20:15
1) Insufficient
p + r = even
p = even r = even. The answer is YES
p = odd r = odd q = even. The answer is NO

2) Insufficient
q + r = odd
q = odd r = even p = even. The answer is YES
q = odd r = even p = odd. The answer is NO

combine 1) and 2) Insufficient
p + r = even
q + r = odd
let r = even, p = even, q=odd. The answer is YES
let r = odd, p = odd, q= even. The answer is NO

Hence E.

GMATD11 wrote:
1) If p,q and r are integers, is pq+r even?

1) p+r is even
2) q+r is add

M getting D

OA is different. Pls confirm if answer is not D
SVP
SVP
avatar
Joined: 16 Nov 2010
Posts: 1673
Location: United States (IN)
Concentration: Strategy, Technology
Followers: 34

Kudos [?]: 471 [0], given: 36

Premium Member Reviews Badge
Re: If p, q, and r are integers, is pq + r even? [#permalink]

Show Tags

New post 10 Mar 2011, 20:22
For pq+r to be even, pq = even and r = even OR pq = odd and r = odd.

From (1)
p + r is even so p is even and r is even or p is odd and r is odd

but no info about q, if q is even and p and r are odd, then pq+r is odd, otherwise even



From (2) , q + r is odd, so q is even and r is odd OR q is odd and r is even

So if p is even, then pq -> even + r (odd) = odd or even + r (even) = even

Not sufficient

Combining both (1) and (2), if p and r ar even, pq + r is even

if p and r are odd then, pq + r is odd (as q is even then)

Hence we don't have definitive answer,and the answer is E.
_________________

Formula of Life -> Achievement/Potential = k * Happiness (where k is a constant)

GMAT Club Premium Membership - big benefits and savings

Verbal Forum Moderator
Verbal Forum Moderator
User avatar
Joined: 10 Oct 2012
Posts: 630
Followers: 76

Kudos [?]: 1008 [0], given: 136

Premium Member
Re: A proper organised way to solve this type of questions? [#permalink]

Show Tags

New post 08 Apr 2013, 05:13
karmapatell wrote:
If p, q, and r are integers, is pq + r even?

(1) p + r is even.
(2) q + r is odd.

Manhattan tells me I should make the table which works fine. I tried doing it without the table and that worked too. However, without the table I was less convinced and more confused because in your head it gets jumbled up. So is there another foolproof way of doing these? Or do I have to stick with the Manhattan table?


From F.S 1, assume p=r=0, thus, we get a YES for the question stem. Now assume p=1, r=1,q = 2 we get a NO. Insufficient.

From F.S 2, assume q=0,r=1, we get a NO for the question stem.Now assume r=2,q=1 ,p=2, we get a YES. Insufficient.

Taking both together, we have p=0,r=0,q=1, and a YES. Again taking, r=1,p=1,q=0, a NO. Insufficient.

What might help you in selecting good numbers is the fact that from the F.S 1,either both p,r are even or both are odd. Similarly, from F.S 2, q and r are odd/even or even/odd.

E.
_________________

All that is equal and not-Deep Dive In-equality

Hit and Trial for Integral Solutions

Current Student
User avatar
Joined: 06 Sep 2013
Posts: 2035
Concentration: Finance
GMAT 1: 770 Q0 V
Followers: 54

Kudos [?]: 515 [0], given: 355

GMAT ToolKit User
Re: If p, q, and r are integers, is pq + r even? [#permalink]

Show Tags

New post 06 Jan 2014, 09:44
karmapatell wrote:
If p, q, and r are integers, is pq + r even?

(1) p + r is even.
(2) q + r is odd.

[Reveal] Spoiler:
Manhattan tells me I should make the table which works fine. I tried doing it without the table and that worked too. However, without the table I was less convinced and more confused because in your head it gets jumbled up. So is there another foolproof way of doing these? Or do I have to stick with the Manhattan table?


Odds and Evens, ok

Statement 1

Clearly Insufficient

Statement 2

Same here

Statements 1 and 2 combined

p+r = even
q+r = odd

p-q = odd

Then p must be even and q odd or the other way around

If p is even then pq will be even and 'r' will be even = All even= Answer is YES
if q is even then pq will again be even and 'r' will be odd= All odd = Answer is NO

Hence E is your best choice

Cheers!
J :)
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 11106
Followers: 511

Kudos [?]: 134 [0], given: 0

Premium Member
Re: If p, q, and r are integers, is pq + r even? [#permalink]

Show Tags

New post 18 Jun 2016, 05:03
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

Re: If p, q, and r are integers, is pq + r even?   [#permalink] 18 Jun 2016, 05:03
    Similar topics Author Replies Last post
Similar
Topics:
2 Experts publish their posts in the topic If P, Q, R, and S are all integers, is product PQRS even? Bunuel 9 17 Feb 2016, 03:13
Experts publish their posts in the topic Which is the greatest among p,q and r? rajthakkar 4 20 Feb 2015, 01:28
4 Experts publish their posts in the topic Is P the youngest of P,Q ,R and S? siddharthamaridi 4 13 Nov 2012, 20:54
4 Experts publish their posts in the topic If P, Q, R, and S are positive integers, and P/Q = R/S, is R rxs0005 9 01 Feb 2011, 11:01
4 Experts publish their posts in the topic If P, Q, R, and S are positive integers, and P/Q = R/S, is R divisible vd 12 02 Jul 2008, 22:20
Display posts from previous: Sort by

If p, q, and r are integers, is pq + r even?

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


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

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®.