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

 It is currently 07 Jul 2015, 10:28

### 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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# If x and y are positive integers, is xy evenly divisible by

Author Message
TAGS:
Senior Manager
Joined: 19 Feb 2004
Posts: 415
Location: Lungi
Followers: 1

Kudos [?]: 8 [0], given: 0

If x and y are positive integers, is xy evenly divisible by [#permalink]  01 Nov 2004, 03:55
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 2 sessions
If x and y are positive integers, is xy evenly divisible by 4?
1. y+2 is divisible by 4.
2. x-2 is divisible by 4.
GMAT Club Legend
Joined: 15 Dec 2003
Posts: 4309
Followers: 29

Kudos [?]: 236 [0], given: 0

C
1) 1 factor of 2 but we know nothing about y
2) 1 factor of 2 but we know nothing about x
both combined, we know that there are 2 factors of 2 in xy
_________________

Best Regards,

Paul

Joined: 31 Dec 1969
Location: India
Concentration: Strategy, Human Resources
GMAT 1: 710 Q49 V0
GMAT 2: 740 Q40 V50
GMAT 3: 700 Q48 V38
GMAT 4: 710 Q45 V41
GPA: 3.31
Followers: 0

Kudos [?]: 93 [0], given: 88362

This is my reason:
-->(a) alone does not tell us anything about X,
But it tells us:
y=4k-2
where
k=1,2,3......
-->(b) alone does not tell us anything about Y
But it tells us:
x=4k+2
where
k=1,2,3.....
+++++
Considering both we can see:
(4k-2)(4k+2)=(16k^2 -4)
=4(4k^2-1)

The above term is divisible by 4 as 4 is a factor of the term.Thus the answer is (c).
Similar topics Replies Last post
Similar
Topics:
3 If x and y are integers, is xy + 1 divisible by 3? 5 09 Dec 2014, 15:02
1 If x and y are positive integers, is y divisible by 3? 8 15 Aug 2011, 05:43
1 Is x an integer? -- x is evenly divisible by 1/2 1 03 Dec 2010, 04:40
If x, y and k are integers, is xy divisible by 3? 2 20 Sep 2009, 18:55
1 If x and y are integers, is xy divisible by 3 ? 1. (x+y)^2 9 27 Apr 2009, 14:51
Display posts from previous: Sort by