Inequality DS

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Inequality DS

by soni_pallavi » Thu Nov 15, 2012 12:58 pm
Interesting DS question

Q) If mv< pv <0 is v>0??

1) m < p

2) m < 0

Could someone plz post an explanation for this?

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by jkaustubh » Thu Nov 15, 2012 8:54 pm
The answer according to me for the above question is D.

According to the question:

mv<pv<0
is V>0 or is V +ve

Now

Statement 1:
m<p

here in the original inequality,
mv<pv<0

this means that mv and pv are -ve

now let us consider the cases:
1. Both m and p are +ve,

then V has to be -ve

however in this case the original inequality will not hold

as mv>pv

so this case is not possible

2. m is -ve and p is +ve

in this case also the original inequality will not hold irrespective of the value of V

Hence this case is also not possible

3. m and p both are -ve

for mv<pv<0

v has to be >0

as m<p, in this case the original inequality stands

Hence statement 1 is sufficient.

Statement 2:

since m<0

and mv<0

V has to be greater that 0

Hence statement 2 is sufficient

Thus the answer is D

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by soni_pallavi » Fri Nov 16, 2012 2:50 am
The answer is D

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by GMAT Kolaveri » Fri Nov 16, 2012 6:18 am
soni_pallavi wrote:Interesting DS question

Q) If mv< pv <0 is v>0??

1) m < p

2) m < 0
Analysis of Question Stem:
V > 0 ?
Yes or No question type.
We need a yes or no for the question whether V lies on the right hand side of zero in the number line?


Statement 1:
m < p
GIVEN: mv< pv <0

if v is -ve , then mv < pv will not be true (when we multiply -ve number we need to flip the signs). v is not negative.
if v is 0, then mv < pv will not be true. v is not Zero.
Hence v is +ve or v > 0. YES
Hence ST 1 is sufficient. BCE can be eliminated.

Statement 2:
Forget everything about statement 1. start fresh with statement 2.
m < 0
GIVEN: mv< pv <0 . m is negative.
if v is -ve, then mv <0 cannot be true. Since the product of two -ve is +ve. v is not negative.
if v is 0, mv < 0 cannot be true. v is not zero.
We have a definite yes for the question is v > 0?

Hence OA: D
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