|
Author |
Message |
|
TAGS:
|
|
|
VP
Joined: 18 May 2008
Posts: 1305
Followers: 9
Kudos [?]:
57
[0], given: 0
|
What is the value of (x - y)^4? (1) The product of x and y [#permalink]
 22 Jun 2008, 06:44
Question Stats:
35% (01:52) correct
64% (00:29) wrong based on 1 sessions
What is the value of (x - y)^4?
(1) The product of x and y is 7.
(2) x and y are integers.
|
|
|
|
|
|
|
Current Student
Joined: 28 Dec 2004
Posts: 3439
Location: New York City
Schools: Wharton'11 HBS'12
Followers: 11
Kudos [?]:
134
[0], given: 2
|
Re: DS: value of (x - y)^4 [#permalink]
22 Jun 2008, 07:07
looks to be C
(x-y)^4?
xy=7..ok, well if x=7 y=1.. you get 6^4..
or you could have x=14 y=1/2 then 13.5^4..isnuff
2) is clearly insuff
together..
xy=7..x and y integers..we know 7 is a prime..so x=7 y=1 or y=7 x=1..either way ans is 6^4
C it is.
|
|
|
|
|
|
Manager
Joined: 22 Jun 2008
Posts: 101
Followers: 3
Kudos [?]:
10
[0], given: 0
|
Re: DS: value of (x - y)^4 [#permalink]
22 Jun 2008, 07:11
ritula wrote: What is the value of (x - y)^4?
(1) The product of x and y is 7.
(2) x and y are integers. Should be C. If x and y are integers and the product of x and y is 7 then we can determine the value of x and y...which is either 1 and 7 or 7 and 1. Both cases generate same value of (x-y)^4, which is 6^4.
|
|
|
|
|
|
Manager
Joined: 21 Mar 2008
Posts: 244
Followers: 2
Kudos [?]:
12
[0], given: 0
|
Re: DS: value of (x - y)^4 [#permalink]
22 Jun 2008, 11:20
The key is that product is a prime number...makes our life easier...Only way to have a product 7 is x=7, y=1 or x=1, y = 7 when both are integers...
Also, an even power for x-y makes it a C....for any off power of x-y, this would have been E, as you will get a positive and a negative solution...
|
|
|
|
|
|
VP
Joined: 18 May 2008
Posts: 1305
Followers: 9
Kudos [?]:
57
[0], given: 0
|
Re: DS: value of (x - y)^4 [#permalink]
22 Jun 2008, 23:25
yes OA is C indeed. thanks !
|
|
|
|
|
|
SVP
Joined: 17 Jun 2008
Posts: 1593
Followers: 7
Kudos [?]:
131
[0], given: 0
|
Re: DS: value of (x - y)^4 [#permalink]
23 Jun 2008, 00:06
Also do not ignore the fact that x and y can be negative (-1 and -7 or -7 and -1). In either case, the answer will be C.
|
|
|
|
|
|
Manager
Joined: 17 Aug 2009
Posts: 241
Followers: 2
Kudos [?]:
61
[1] , given: 25
|
Re: DS: value of (x - y)^4 [#permalink]
09 Dec 2009, 09:40
1
This post received
KUDOS
Statement 1 ---------------Insufficient
X can be 7 when Y is 1 or X can be 1/7 when Y is 7 and so on……
Multiple answers, hence insufficient
Statement 2 --------------CLEARLY INSUFFICIENT (No info about the numbers)
Combining the two,
Since they are both integers and 7 happens to be a prime number divisible by 1 and 7 only, the numbers are 7 and 1
Whether y is 7 or 1 (Same with x), does not matter as the power (4 in this case) is even which will give the same positive result
|
|
|
|
|
|
Intern
Joined: 10 Sep 2011
Posts: 7
Followers: 0
Kudos [?]:
2
[0], given: 0
|
Re: DS: value of (x - y)^4 [#permalink]
18 Sep 2011, 03:32
i have to say nice question..totally deceive me....
|
|
|
|
|
|
Manager
Status: Retaking next month
Affiliations: None
Joined: 05 Mar 2011
Posts: 232
Location: India
Concentration: Marketing, Entrepreneurship
GMAT 1: 570 Q42 V27
GPA: 3.01
WE: Sales (Manufacturing)
Followers: 3
Kudos [?]:
12
[0], given: 32
|
Re: DS: value of (x - y)^4 [#permalink]
18 Sep 2011, 21:15
Looks like a straight C. 
|
|
|
|
|
|
|
Re: DS: value of (x - y)^4
[#permalink]
18 Sep 2011, 21:15
|
|
|
|
|
|
|
|
|
|
|
close
