Data Sufficiency

If m*v < p*v < 0 , is it v > 0 ?

1) m < p

2) m < 0

B

from the stem, we know that both m*v and p*v are negative, which means that one of the terms in each combo is negative. so we have to find which term is negative.

1) v doesn't necessarily have to be positive. say m = 5 and p = 6, so v can be any number in this case. on the other hand, say v = 1, and m = -6, p = -5.
INSUFFICIENT

2) if m is negative, then v has to be positive to make m*v negative.
SUFFICIENT.

CIAO1982 wrote:If m*v < p*v < 0 , is it v > 0 ?

1) m < p

2) m < 0

mv<pv<0 implies mv-pv<0, i.e. v(m-p)<0

This is possible when either
v<0 and (m-p)>0, i.e. m>p
or, v>0 and (m-p)<0, i.e., m<p

Stm 1: m<p, so v>0 suff
Stm2: m<0...tells us nothing about p, hence in suff

Answer is A

Neeraj is correct for stm2
...looks like answer is D

Sorry I didn't give you the answer.

Actually it is D.

mv<pv<0 is the stem !....

it is also true

pv<0

and pv>mv or p>m

A) it stating the same thign as stem ! no info on v, we know pv<0 but not p or v !!

Insuff

B)m<0 !! m is -ve !!

m * v !, v has to positive !!

if not mv will never be < 0

IMO B

vishubn wrote:mv<pv<0 is the stem !....

it is also true

pv<0

and pv>mv or p>m

A) it stating the same thign as stem ! no info on v, we know pv<0 but not p or v !!

Insuff

B)m<0 !! m is -ve !!

m * v !, v has to positive !!

if not mv will never be < 0

IMO B

I am not sure if we can say pv>mv or p>m because we do not know if v is +ve or -ve, but we can definitely say pv-mv>0...my two cents

It's D : From the stem we know mv<pv<0

Which means : V can be negative or positive depending on M and P

If M is positive V is negative => P is positive and for the stem to be true m<p
If m is negative v is positive and P is negative but for the stem to be true m>p.

Now from 1: m<p => v < 0 Sufficient

From 2 : m<0 => p<0, m>p and v > 0 : Sufficient

- pradeep

Good solutions All!

I would also like to share Ian's approach for Stmt I

mv < pv

m<p

Multiply both sides by v.If v was negative then it would make mv>pv since the inequality reverseS when u multiply by a negative number but its given mv<pv so v has to be positive.

SUFF

pbanavara wrote:It's D : From the stem we know mv<pv<0

Which means : V can be negative or positive depending on M and P

If M is positive V is negative => P is positive and for the stem to be true m<p
If m is negative v is positive and P is negative but for the stem to be true m>p.

Now from 1: m<p => v < 0 Sufficient

From 2 : m<0 => p<0, m>p and v > 0 : Sufficient

- pradeep

Hey Bro !

I liked ur conversation with ur penguin

vishu