We have to determine whether a/b > 0.M7MBA wrote:Is a/b > 0?
(1) ab > 0
(2) b/a > 0
The OA is D.
How can I prove that each statement alone is sufficient? Should I use particular numbers or it can be solved for a and b general?
Let's take each statement one by one.
(1) ab > 0
=> a and b both are either postive or negative.
Case 1: Say a and b both are postive, then we have a/b = |a|/|b| = positive quantity > 0. The answer is Yes.
Case 2: Say a and b both are negative, then we have a/b = (-|a|) / (-|b|) = |a|/|b| = positive quantity > 0. The answer is Yes.
Sufficient.
(2) b/a > 0
=> a and b both are either postive or negative.
Case 1: Say a and b both are postive, then we have a/b = |a|/|b| = positive quantity > 0. The answer is Yes.
Case 2: Say a and b both are negative, then we have a/b = (-|a|) / (-|b|) = |a|/|b| = positive quantity > 0. The answer is Yes.
Sufficient.
The correct answer: D
Hope this helps!
-Jay
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