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shubhamkumar
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ab/cd < 0 implies either ab = positive and cd = negative OR ab = negative and cd = positive, which ab and cd have opposite signs.shubhamkumar wrote:IF ab/cd<0 is bc>ad?
1) cd>ab
2) b<c<0
OA B
(1) cd > ab and we know that ab and cd have opposite signs, so cd > 0 and ab < 0. This means that c and d are both positive or both negative, but a and b are of opposite signs.
Case I: If c, d, and b are positive and a = negative, then bc > 0 and ad < 0. So, here bc > ad.
Case II: If c, d, and a are positive and b = negative, then bc < 0 and ad > 0. So, here bc < ad.
No definite answer; NOT sufficient.
(2) b < c < 0 implies bc > 0
ab/cd < 0 implies (b/c) * (a/d) < 0
Since bc > 0 , so ad < 0, which implies bc > ad; SUFFICIENT.
The correct answer is B.
