Summer is Coming! Join the Game of Timers Competition to Win Epic Prizes. Registration is Open. Game starts Mon July 1st.

 It is currently 19 Jul 2019, 16:31

### 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

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

# If r and s are both positive integers, is the product of r and s even?

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 56300
If r and s are both positive integers, is the product of r and s even?  [#permalink]

### Show Tags

21 Aug 2018, 13:22
00:00

Difficulty:

35% (medium)

Question Stats:

70% (00:55) correct 30% (00:49) wrong based on 37 sessions

### HideShow timer Statistics

If r and s are both positive integers, is the product of r and s even?

(1) r and s are consecutive integers.

(2) (s - 1) is a prime number greater than 3.

_________________
Intern
Joined: 03 Sep 2017
Posts: 10
Location: India
GMAT 1: 720 Q47 V42
GPA: 3.4
Re: If r and s are both positive integers, is the product of r and s even?  [#permalink]

### Show Tags

21 Aug 2018, 13:31
S1: out of two consecutive integers, one will always be even, hence their product will be even. Sufficient

S2: any prime number greater than 3 is odd and hence will be followed by an even number. Hence s-1 is odd and s is even. Hence, the product of r and s will be even. Sufficient.

I vote that the answer is d

Posted from my mobile device
Director
Joined: 20 Feb 2015
Posts: 790
Concentration: Strategy, General Management
If r and s are both positive integers, is the product of r and s even?  [#permalink]

### Show Tags

Updated on: 21 Aug 2018, 13:41
Bunuel wrote:
If r and s are both positive integers, is the product of r and s even?

(1) r and s are consecutive integers.

(2) (s - 1) is a prime number greater than 3.

(1) r and s are consecutive integers.
This case will always result in an even number
sufficient.

(2) (s - 1) is a prime number greater than 3.
say
s=6
as even * odd/even=even

D

corrected thanks !!

Originally posted by CounterSniper on 21 Aug 2018, 13:35.
Last edited by CounterSniper on 21 Aug 2018, 13:41, edited 1 time in total.
Intern
Joined: 03 Sep 2017
Posts: 10
Location: India
GMAT 1: 720 Q47 V42
GPA: 3.4
Re: If r and s are both positive integers, is the product of r and s even?  [#permalink]

### Show Tags

21 Aug 2018, 13:38
1
CounterSniper wrote:
Bunuel wrote:
If r and s are both positive integers, is the product of r and s even?

(1) r and s are consecutive integers.

(2) (s - 1) is a prime number greater than 3.

(1) r and s are consecutive integers.
This case will always result in an even number
sufficient.

(2) (s - 1) is a prime number greater than 3.
say
s=6
r=?
insufficient .

A

I don't think the value of r should matter if it's proved that s is even, since any number multiplied by an even number is even

Posted from my mobile device
VP
Joined: 31 Oct 2013
Posts: 1392
Concentration: Accounting, Finance
GPA: 3.68
WE: Analyst (Accounting)
If r and s are both positive integers, is the product of r and s even?  [#permalink]

### Show Tags

21 Aug 2018, 13:56
Bunuel wrote:
If r and s are both positive integers, is the product of r and s even?

(1) r and s are consecutive integers.

(2) (s - 1) is a prime number greater than 3.

we are looking for the the product of rs, whether it's even or not.

Statement 1: r ans s are consecutive integers. r= 2 s = 3. rs = 6. Sufficient.

Statement 2: s - 1 = prime. Note: only even prime is 2. So, s has to be an even number for sure. even * odd / even = even .

Director
Joined: 06 Jan 2015
Posts: 681
Location: India
Concentration: Operations, Finance
GPA: 3.35
WE: Information Technology (Computer Software)
Re: If r and s are both positive integers, is the product of r and s even?  [#permalink]

### Show Tags

21 Aug 2018, 19:52
Bunuel wrote:
If r and s are both positive integers, is the product of r and s even?

(1) r and s are consecutive integers.

(2) (s - 1) is a prime number greater than 3.

r*s =?

(1) r and s are consecutive integers.

For any consecutive integers one has to be even and odd

Hence even*odd=even

Suff

(2) (s - 1) is a prime number greater than 3

If (s-1) is prime number s has to be even

Hence Suff

Hence D
_________________
आत्मनॊ मोक्षार्थम् जगद्धिताय च

Resource: GMATPrep RCs With Solution
Re: If r and s are both positive integers, is the product of r and s even?   [#permalink] 21 Aug 2018, 19:52
Display posts from previous: Sort by