Stmt I
x/y = 1 (i.e x=y)
x=2 y=2
x=1 y=1
INSUFF
Stmt II
xy = 1
x=2 y=1/2
x=4y=1/4
x=1 y=1
INSUFF
Stmt I and II together
X/Y=1 I.E X=Y
XY=1
X^2 = 1
sqrt(x^2) = sqrt(1^2) (sqrt(x^2) = |x|)
|X| = 1
X=1 OR X=-1 Given x is positive so x=1
Not necessary for this problem but y=1 also
Same for y
y^2 = 1
|y| = 1
y=1 or y=-1 but since y is positive and greater than 0 y=1
SUFF
C)
xy DS question
This topic has expert replies
Source: Beat The GMAT — Data Sufficiency |
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cramya
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Tj,
Thanks for posting the official answer. For the futrue problems if u could hide the OA using spoiler function then that would be much appreciated.
OA: C
This way the users will not know the answers before solving the problem as it takes the fun out of it....
Good luck!
Regards,
Cramya
Thanks for posting the official answer. For the futrue problems if u could hide the OA using spoiler function then that would be much appreciated.
OA: C
This way the users will not know the answers before solving the problem as it takes the fun out of it....
Good luck!
Regards,
Cramya
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vittalgmat
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Stmt1: x/y = 1.tj123 wrote:If x and y are greater than 0, is x= 1?
1) x/y = 1
2) xy= 1
Answer is C) Both
Please explain.
Here x and y can be any number (+ve int, frac, irrational#)
as long as x =y
OR it x and y both could be 1.
So insufficient.
stmt2: xy = 1.
Again x and y can be reciprocal of each other.
ie y = 1/x.
xy =1 => x * 1/x = 1
OR both x and y could be 1.
So insufficient.
Combining 1 and 2.
Now this will eliminate the x = y case from stmt 1 and reciprocal case from stmt2. The only remaining case is x=y =1
So answer is C
HT Helps
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ronniecoleman
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Although IMO C
but please submitter....don't post the OA with the question..
Follow the rules !
but please submitter....don't post the OA with the question..
Follow the rules !
Admission champion, Hauz khaz
011-27565856
011-27565856
