Inequalities 2

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by samirpandeyit62 » Sun Sep 30, 2007 10:01 am
y < x+z/2

i.e 2y < x+z

stmt 1: y-z < z -y

i.e 2y <2z

i,e y<z

we cannot say this x>z or z>x

NOT SUFF

stmt2: z-y>z-x/2

i.e 2z -2y > z-x

i.e 2z -z +x > 2y

i.e 2y <z+x

SUFF

ans shoud be B
Regards
Samir

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by jay2007 » Mon Oct 01, 2007 2:54 pm
1) y-z = z-y
y<z NOT sufficient. We don't know about x.

2) z-y > z-x/2
-y > -x/2
y<x/2 - NOT sufficient. We don't know about z.

1 & 2
2y < z+x/2 => y<z/2+x/4

If x=0, then y<x+z/2 = y<x/4+z/2
But if x!=0 then <x+z/2 is not equal to y<x/4+z/2. Therefore 1 & 2 are not sufficient.

Answer is E.
Please correct me if am wrong.

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by kajcha » Tue Oct 02, 2007 9:20 am
jay2007 wrote: 2) z-y > z-x/2
.
I think the stmt 2 should read like

z-y > (z-x)/2. If this is the case then Ans is B

Please confirm the OA