If x and y are integers and x<y, what is the value of x+y?
(1) x^y=4
(2) |x|=|y|
5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
nice one by MGMAT !
This topic has expert replies
-
hemant_rajput
- Master | Next Rank: 500 Posts
- Posts: 447
- Joined: Sun Apr 22, 2012 7:13 am
- Thanked: 46 times
- Followed by:13 members
- GMAT Score:700
1. Possible values of x and y are -himu wrote:If x and y are integers and x<y, what is the value of x+y?
(1) xy=4
(2) |x|=|y|
x = -4 and y = -1
x = 1 and y = 4.
so there are 2 possible values of x+y, -5 and 5.
Hence Not sufficient.
2.
absolute value of x and y is same, also x<y i.e. x = -y.
hence x + y = x - x = 0.
Hence sufficient.
[spoiler]Answer:B[/spoiler]
I'm no expert, just trying to work on my skills. If I've made any mistakes please bear with me.
-
GMATGuruNY
- GMAT Instructor
- Posts: 15539
- Joined: Tue May 25, 2010 12:04 pm
- Location: New York, NY
- Thanked: 13060 times
- Followed by:1906 members
- GMAT Score:790
Statement 1: x^y=4.himu wrote:If x and y are integers and x<y, what is the value of x+y?
(1) x^y=4
(2) |x|=|y|
Given that x and y are integers, the only values of x and y such that x^y=4 and x<y are x=-2 and y=2.
Thus, x+y = -2+2 = 0.
SUFFICIENT.
Statement 2: |x| = |y|
Since both sides of the equation include absolute value, we can square both sides.
|x|² = |y|²
x² = y²
x²-y² = 0.
(x+y)(x-y) = 0.
Case 1: x+y=0.
Case 2: x-y=0, implying that x=y.
Since the question stem requires that x<y, case 2 is not valid.
Thus, x+y=0.
SUFFICIENT.
The correct answer is D.
Last edited by GMATGuruNY on Fri May 10, 2013 5:07 am, edited 2 times in total.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
-
hemant_rajput
- Master | Next Rank: 500 Posts
- Posts: 447
- Joined: Sun Apr 22, 2012 7:13 am
- Thanked: 46 times
- Followed by:13 members
- GMAT Score:700
I'm posting the explanation for edited 1st option.
(-2)^2 = 4 then -2 + 2 = 0
Hence sufficient.
Answer is D
(-2)^2 = 4 then -2 + 2 = 0
Hence sufficient.
Answer is D
Last edited by hemant_rajput on Fri May 10, 2013 10:43 am, edited 1 time in total.
I'm no expert, just trying to work on my skills. If I've made any mistakes please bear with me.
-
GMATGuruNY
- GMAT Instructor
- Posts: 15539
- Joined: Tue May 25, 2010 12:04 pm
- Location: New York, NY
- Thanked: 13060 times
- Followed by:1906 members
- GMAT Score:790
I've edited my explanation accordingly.himu wrote:Thanks so much for your replies.
My Bad, but the copy-paste omitted the "raised to ^ " sign in statement I.
have edited the same now.
CHeers,
~Himu.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
