Is |a| = b - c ? (1) a + c does not equal b (2) a

Question

Is |a| = b - c ?

(1) a + c does not equal b
(2) a < 0

jackb24 · Answer

1) Simpliy Question
 is a = b -c => a+c =b
 or -a = b-c => c-a = b
 It is a 2 part question a+c =b? or c-a=b?
2) Evaluate 1.
 Insufficiant We dont know if c-a = b
3) Evaluate 2.
 Insufficient we dont know the value of a and b
4) Evaluate 1 and 2 together
 1. a+c != b
 2. a is -ve so c-(-a)=> C+a =b? 1 says it is not
 Sufficient to answer that |a|!=b -c

Ans C.

IanStewart · Answer

If a = -1, b=0, and c=0, then both statements are true, and the answer to the question is 'no'.

If a = -1, b = 1 and c = 0, then both statements are true, and the answer to the question is 'yes'.

The answer is E.

rjkaufman21 · Answer

Thank you for the example Ian. I thought it was E as well, and wanted to see if I was missing something.

This question comes from Jeff Sackmans extreme challenge. He has C listed as the answer. I'm going to shoot him an e-mail and see if he responds. Looks like an error.

Thanks.

amit2k9 · Answer

for a=-1|1 ,b=3|5, c=2

a false for a=1,b=5,c=2 but true for a=1,b=3,c=2. not sufficient.

b same for a=-1 and with different b values of 3 and 5. not sufficient.

a+b not sufficient for a=-1 b= 3|5 , c=2. 
E it is.

blink005 · Answer

E

1 & 2 are obviously insufficient alone
so we can eliminate a,b,d

between c & e

As Ian pointed out, there may or may not be an equality

Hence E

liftoff · Answer

Both statement one and two gives no information about "b"
Therefore they are insufficient. Even together they dont give info about "b"

GMATmission · Answer

E for me. statement 1 and statement 2 are basically giving the same information.

rjkaufman21 · Answer

Sackmann never wrote me back. Oh well.

gautammalik · Answer

I also feel answer should be E
a+c = d and d != n
it does not matter whether a is positive or negative.

bumpbot · Answer

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Is |a| = b - c ? (1) a + c does not equal b (2) a < 0

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