1) IF m < p, mv < pv if v > 0.

For eg -3 < -2 and if v = +1, inequality remains so. But if v = -1, inequality is inverted. Hence v has to be greater than 0.

2) if mv < 0, and m < 0. Then v is greater than 0 else mv would change sign and be greater than 0.

Akansha wrote:If mv < pv < 0, is v > 0?
a. m < p
b. m < 0

OA is D

I) m < p
m -p < 0
mv < pv
v(m-p)<0
as, m-p<0
So,v>0
Sufficient.

II)m<0
as,mv<0 and m<0
So,v>0
Sufficient.

D it is.

mv<pv<0
(m-p)v<0
thus either v<0 or m<p
a) m<p now if both m,p are positive, to satisfy mv<0, v <0 but then mv<pv won't be satisfied
if both m and p are -ve, v>0 possible
Also both m and p should be of same sign (as mv,pv are both <0)
Thus A is sufficient (m and p should be <0 and v is greater than 0)
b)m<0 to satisfy mv<0, v should be greater than 0.
sufficient.
IMO D

mv<pv<0
this means,v(m-p)<0
so either v<0or m-p<0 which means m<p
a.m<p this implies v<0.so this condition alone is sufficient
b.m<0means v>0 so this condition alone is also sufficient.
hence the answer is D