mba4me wrote:
|x| >= |x-y| + |y|, is y > x?
1. x > 0
2. y > 0
This question has already been posted earlier. I somehow dont agree with the OA.
By 1)
(5,2)
|5| >= |5-2| + |2|
5 >= 3 + 2, satisfy the equation, y=2, which is smaller than x, our answer to is y>x? is NO
(5,6)
|5| >= |5-6| + |6|
5 >= 1 + 6, does not satisfy the equstion
(5,-1)
|5| >= |5-(-1)| + |-1|
5 >= 6 + 1, does not satisfy the equation
(5, -5)
|5| >= |5-(-5)| + |-5|
5 >= 0 + 5, satisfy the equation, y=-5, which is smaller than x, our answer to is y>x? is NO
(5, 0)
|5| >= |5-0| + |0|
5 >= 5 + 0, satisfy the equation, y=0, which is smaller than x, our answer
to is y>x? is NO
(5, -6)
|5| >= |5-(-6)| + |-6|
5 >= 11 + 6, does not satisfy the equation
By 1) alone, all the answers we get is NO, so it is sufficient.
By 2)
(5,2)
|5| >= |5-2| + |2|
5 >= 3 + 2, satisfy the equation, x=5, which is greater than y, our answer to is y>x? is YES
(-5,2)
|-5| >= |-5-2| + |2|
5 >= 7 + 2, does not satisfy the equation
(0,2)
|0| >= |0-2| + |2|
0 >= 2 + 2, does not satisfy the equation
(-1, 2)
|-1| >= |-1-2| + |2|
1 >= 3 + 2, does not satisfy the equation
(2,2)
|2| >= |2-2| + |2|
2 >= 0 + 2, satisfy the equation, x=0, our answer to is y>x? is NO
(1,2)
|1| >= |1-2| + |2|
1 >= 1 + 2, does not satisfy the equation
By 2) alone, we get both YES and NO for the answer, so it is not sufficient.
My answer is A