Is ab < 12?
(1) a < 3 and b < 4
(2) 1/3 < a < 2/3 and b^2< 169
The OA is B .
I am a little confuse here. Experts, may you help me please? I would be really thankful.
Is ab < 12?
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Statement 1 - Case 1: a = 2 and b = 3. ab = 6, and the answer is YES ab < 12.M7MBA wrote:Is ab < 12?
(1) a < 3 and b < 4
(2) 1/3 < a < 2/3 and b^2< 169
The OA is B .
I am a little confuse here. Experts, may you help me please? I would be really thankful.
Case 2: a = -5 and b = -6. ab = 30, and the answer is NO ab is not less than 12. S1 alone is not sufficient.
Statement 2: We could pick numbers here as well, but we could also use a little logic. If b^2 < 169 then b < |13|. So we know that ab is between 1/3 and 2/3 of a value that is < |13|. Well 2/3 of 13 is itself less than 12, so if we're talking about a product in we're multiplying a positive value less than 2/3 and a value less than 13, the product will always be less than 12, and the answer to the question is always YES. Statement 2 alone is sufficient. The answer is B