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Zumit Ds 007
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05 Sep 2008, 22:01
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Re: Zumit Ds 007
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05 Sep 2008, 22:31
dancinggeometry wrote: Is x  z > x  y ?
(1) z > y (2) 0 > x E scenario 1: x = 1 , y = 4, z = 5, then x  z > x  y scenario 2: x = 1, y= 4, z = 5, then NOT x  z > x  y



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Re: Zumit Ds 007
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05 Sep 2008, 22:44
dancinggeometry wrote: Is x  z > x  y ?
(1) z > y (2) 0 > x (2) if x<0 question : zx>yx => z,y unknown cannot say INSUFFI (1)z>y => say z=2 ,y=1 x=1 => x  z > x  y is true when z=3 x=1 ,y=2 => x  z > x  y is false (1) and (2) => SUFFI x is always ve ,hence since z>y zx>yx IMO C
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Re: Zumit Ds 007
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06 Sep 2008, 12:43
C cannot be correct:
take for instance
x = 5 z = 2 y = 1
Here 5 2  > 5  (1)
7 > 4
x = 5 z = 2 y = 1
Here 5 (2)  > 5  1
3 < 6
Hence Answer is E
Another way IMO to do this is by plotting numbers on a number line
I z II y III 0 IV y V z VI <>
x could be in any of I through VI
In various scenarios the distance between x and z could be greater or less than the distance between x and y



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Re: Zumit DS 007
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06 Sep 2008, 23:42
OA is E.
Statement (1) is not sufficient. Consider, for example, the following: if x,y, and z are 3, 4,and 5, xz=8 and xy=7 BUT if x, y, and z were 3, 4, and 5, then xz=2 and xy=7 In both cases, z>y, but the answer to the original question changes.
Statement (2) is not sufficient either. We know that x is negative, but we are told nothing about y and z
Combined, the statements are still insufficient. In both cases used for (1), x is negative, but we get different answers to the question.



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Re: Zumit Ds 007
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07 Sep 2008, 10:50
ok spriya, i suggest u understand what is being asked. the stem asked is (the distance betn x and z) x  z > x  y(distance betn x and y) ??
stat 1) z > y. this means that the dist betn 0 and z > dist betn 0 and y. __________2(z)__________1____(x)_____0__________y(1)______________clearly x can be equidistant from both y and z. insuff.
stat 2) x is ve . we can use the above example itself to refute the requirement.
both stat will not help E



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Re: Zumit Ds 007
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07 Sep 2008, 18:15
arjtryarjtry wrote: ok spriya, i suggest u understand what is being asked. the stem asked is (the distance betn x and z) x  z > x  y(distance betn x and y) ??
stat 1) z > y. this means that the dist betn 0 and z > dist betn 0 and y. __________2(z)__________1____(x)_____0__________y(1)______________clearly x can be equidistant from both y and z. insuff.
stat 2) x is ve . we can use the above example itself to refute the requirement.
both stat will not help E ok ! i think i got to substitute values !!!
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Re: Zumit Ds 007
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07 Sep 2008, 23:44
For such questions, number line helps me understand better.
Stmt 1 and 2 independently are not sufficient.
Combining the two.
Case 1: y and z are to the right of 0
!!!! X 0 Y Z
In this case zx > yx
Case 2: y and z are to the left of 0 (and say to the left of x)
!!!! Y Z X 0
Here zx < yx
Case 3: y and z are to the left of 0 (and say to the right of x)
!!!! X Y Z 0
Here zx > yx
Thus, cobining two statements also gives different results. Hence, E.



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Re: Zumit Ds 007
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08 Sep 2008, 01:20
dancinggeometry wrote: Is x  z > x  y ?
(1) z > y (2) 0 > x Can we write x  z as x  z ? I guess No. So if we know only that z > y can we safely assume that the given information is insufficient ? Thanks
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Re: Zumit Ds 007
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08 Sep 2008, 01:26
amitdgr wrote: dancinggeometry wrote: Is x  z > x  y ?
(1) z > y (2) 0 > x Can we write x  z as x  z ? I guess No. So if we know only that z > y can we safely assume that the given information is insufficient ? Thanks xz = x  z will not always be true. This will be true only if both x and z are positive or both are negative and x > z. == Message from GMAT Club Team == This is not a quality discussion. It has been retired. If you would like to discuss this question please repost it in the respective forum. Thank you! To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative  Verbal Please note  we may remove posts that do not follow our posting guidelines. Thank you.




Re: Zumit Ds 007 &nbs
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08 Sep 2008, 01:26






