a. 2x - 2y = 1
b. x�y > 1
OA: C
Detailed explanations would be helpful! Thanks
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X and Y both positive?
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sreak1089
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Qn: Are x & y both +ve?
Stmt # 1: 2x - 2y = 1
=> 2(x-y) = 1
=> x-y = 1/2
it means (x-y) > 0
we can further deduce that x > y
This is still NOT SUFFICIENT as x & y can both be +ve or can both be -ve.
Stmt # 2: x/y > 1
Two cases exist: a) x & y both +ve with x > y
b) x & y both -ve with x < y
This is still NOT SUFFICIENT as x & y can both be +ve or both can be -ve.
Combining 1 & 2, we have can only have one case which is x & y both +ve with x > y.
Hence the answer is C
Stmt # 1: 2x - 2y = 1
=> 2(x-y) = 1
=> x-y = 1/2
it means (x-y) > 0
we can further deduce that x > y
This is still NOT SUFFICIENT as x & y can both be +ve or can both be -ve.
Stmt # 2: x/y > 1
Two cases exist: a) x & y both +ve with x > y
b) x & y both -ve with x < y
This is still NOT SUFFICIENT as x & y can both be +ve or both can be -ve.
Combining 1 & 2, we have can only have one case which is x & y both +ve with x > y.
Hence the answer is C
