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x y z are Three integers is x>y>z? 1) [#permalink]
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16 Sep 2007, 18:24
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x y z are Three integers is x>y>z?
1) zx=zy+yz
2) z>x



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Re: x y z are Three integers is x>y>z? [#permalink]
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16 Sep 2007, 19:37
studentnow wrote: x y z are Three integers is x>y>z?
1) zx=zy+yz 2) z>x
should be B. if z > x, then definitely x>y>z.



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Re: x y z are Three integers is x>y>z? [#permalink]
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16 Sep 2007, 19:40
Fistail wrote: studentnow wrote: x y z are Three integers is x>y>z?
1) zx=zy+yz 2) z>x should be B. if z > x, then definitely x>y>z.
How?
If Z > X then how would X > Y > Z ?
 Brajesh



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If z = x+2, y = x+1, then
St1:
zx = zy + yz
x+2x = x+2x1  x+1x2
2 = 1 + 1
If z = x2, y = x1, then
zx = zy + yz
x2x = x2x+1 + x1x+2
2 = 1 + 1
So can be x > y > z, or x < y <z>x. Nothing else about y. x could be = y, or <y> y. Insufficient.
St1 & St2:
z = x+2, y = x+1, then zx = zy + yz ( x < y < z)
Only x<y<z yields a solution that fit st1 and st2. The rest do not yield such a solution.
Ans C



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Re: x y z are Three integers is x>y>z? [#permalink]
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16 Sep 2007, 22:11
b14kumar wrote: Fistail wrote: studentnow wrote: x y z are Three integers is x>y>z?
1) zx=zy+yz 2) z>x should be B. if z > x, then definitely x>y>z. How? If Z > X then how would X > Y > Z ?  Brajesh
if z>x, then x cannot be grater than z. so suff...
do not need st. 1.



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Re: x y z are Three integers is x>y>z? [#permalink]
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16 Sep 2007, 22:17
Fistail wrote: b14kumar wrote: Fistail wrote: studentnow wrote: x y z are Three integers is x>y>z?
1) zx=zy+yz 2) z>x should be B. if z > x, then definitely x>y>z. How? If Z > X then how would X > Y > Z ?  Brajesh if z>x, then x cannot be grater than z. so suff... do not need st. 1.
You said:
if z > x, then definitely x>y>z
I thought you were saying that if z > x then x>y>z would be true.
However, I think you meant to say that x>y>z would not be true....ST2 is sufficient to answer the question.....That is what you meant...Right?
 Brajesh



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Re: x y z are Three integers is x>y>z? [#permalink]
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16 Sep 2007, 23:55
studentnow wrote: x y z are Three integers is x>y>z?
1) zx=zy+yz
2) z>x
I get D.
Start w/ S2. S1 looks ugly.
z>x, well then x>y>z can't be true.
S1.
zx=zy+yz> zx=0. z has to equal x.
z+x=z+y y+z. z+x=0> xz=0 x=z.



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Re: x y z are Three integers is x>y>z? [#permalink]
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17 Sep 2007, 03:08
[quote="studentnow"]x y z are Three integers is x>y>z?
1) zx=zy+yz
2) z>x[/quote]
I think it is E
1) zx=zy+yz => zx=zy+zy=2zy=>there are many combinations=>insufficient
2) z>x=>insufficient
1&2) zx=2zy=> a) zx=2z2y=>x=2yz or b) xz=2z2y=>x=z2y we have at least two combinations=> so insufficient
Changed my opinion to B
Last edited by Vlad77 on 17 Sep 2007, 04:50, edited 1 time in total.



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Should be 'B'
stmt1: INSUFF
take x =5 , y =3, z =1 satisfies stmt1
x=3 , y =3, z=1 also satisfies stmt1
Stmt2; suff
as Z>x, this means that x>y>z can never be true.



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I will go with B as well. What is the OA.
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Subhen



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vshaunak@gmail.com wrote: Should be 'B'
stmt1: INSUFF take x =5 , y =3, z =1 satisfies stmt1 x=3 , y =3, z=1 also satisfies stmt1
Stmt2; suff as Z>x, this means that x>y>z can never be true.
oops ya change to B from D



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Re: x y z are Three integers is x>y>z? [#permalink]
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17 Sep 2007, 10:43
b14kumar wrote: Fistail wrote: b14kumar wrote: Fistail wrote: studentnow wrote: x y z are Three integers is x>y>z?
1) zx=zy+yz 2) z>x should be B. if z > x, then definitely x>y>z. How? If Z > X then how would X > Y > Z ?  Brajesh if z>x, then x cannot be grater than z. so suff... do not need st. 1. You said: if z > x, then definitely x>y>z I thought you were saying that if z > x then x>y>z would be true. However, I think you meant to say that x>y>z would not be true....ST2 is sufficient to answer the question.....That is what you meant...Right?  Brajesh
thats absolutely right.




Re: x y z are Three integers is x>y>z?
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17 Sep 2007, 10:43






