Is absolute value A + abslute value B > ABSOLUTE VALUE a+B?
1. a^2 > b^2
2. Absolute value a * b < 0
I chose d but answer to my slap in the face was E
manhatan gmat ds
This topic has expert replies
Please confirm if I have got the question right...
Is Abs(A) + Abs(B) > Abs(A + B)?
The only cases this is possible are when A and B have different signs. If A & B have the same sign both sides of the equation will be equal.
St 1
A^2 > B^2
This statement reveals nothing about the sign of A & B. In other words all possible combinations of +ve and +ve numbers for A & B will satisfy St 1. So INSUFF, leaves us with B, C & E
St 2
Abs(A) * B < 0
So, B is ve. But A could be both +Ve and ve So INSUFF, leaves us with C & E
Taking 1 & 2 together, we still cannot determine the sign for A. So E
Is Abs(A) + Abs(B) > Abs(A + B)?
The only cases this is possible are when A and B have different signs. If A & B have the same sign both sides of the equation will be equal.
St 1
A^2 > B^2
This statement reveals nothing about the sign of A & B. In other words all possible combinations of +ve and +ve numbers for A & B will satisfy St 1. So INSUFF, leaves us with B, C & E
St 2
Abs(A) * B < 0
So, B is ve. But A could be both +Ve and ve So INSUFF, leaves us with C & E
Taking 1 & 2 together, we still cannot determine the sign for A. So E

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The best way to approach these problems is by using a number line and to think.
Basically you need to find out the signs of A and B. This is because if they are on opposite sides of the number line, the lAl + lBl will always = lA+Bl
If they are on the same side, lAl + lBl always > lA+Bl
1) Does not tell you about signs. Insignificant
2) Tells you B is negative, but does not tell you about A's sign
IMO E.
Just practice using number lines and these problems will get a lot easier.
Basically you need to find out the signs of A and B. This is because if they are on opposite sides of the number line, the lAl + lBl will always = lA+Bl
If they are on the same side, lAl + lBl always > lA+Bl
1) Does not tell you about signs. Insignificant
2) Tells you B is negative, but does not tell you about A's sign
IMO E.
Just practice using number lines and these problems will get a lot easier.

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Mike mentioned an important takeawaymike22629 wrote:The best way to approach these problems is by using a number line and to think.
Basically you need to find out the signs of A and B. This is because if they are on opposite sides of the number line, the lAl + lBl will always = lA+Bl
If they are on the same side, lAl + lBl always > lA+Bl
1) Does not tell you about signs. Insignificant
2) Tells you B is negative, but does not tell you about A's sign
IMO E.
Just practice using number lines and these problems will get a lot easier.
I have highlighted it.
Thanks Mike.