Absolute DS
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oh i did this question wrong i thought the answer to this would be B but its not the case i rectified my mistake after looking the solutions posted here.i did it in a hurry and ended up with a wrong answer
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This is a smple problem.
Q. asks if x = a-b AND b-a simultaneously.
1) x= a-b ------->not sufficient.
2) x= b-a (or, -(a-b)--------->not sufficient.
but 1&2 together is sufficient since one states x=a-b and the other states x=b-a.
Hence C.
Q. asks if x = a-b AND b-a simultaneously.
1) x= a-b ------->not sufficient.
2) x= b-a (or, -(a-b)--------->not sufficient.
but 1&2 together is sufficient since one states x=a-b and the other states x=b-a.
Hence C.
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gmatusa2010 ur method of the trial and error is perfectly right in this sum...
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Is |X|= A - B?
1. X = A - B
2. X = B - A
1. INSUFFICIENT. Because, A-B can be positive or negative
2. INSUFFICIENT. Because, B-A can be positive or negative
Note: Negative A-B or B-A will mean that the A-B or B-A will become B-A or A-B if either is negative.
COMBINED, we know X = A - B = B - A ; which means A=B=X=0. (Not sure if there is any other value?)
ANSWER: C.
1. X = A - B
2. X = B - A
1. INSUFFICIENT. Because, A-B can be positive or negative
2. INSUFFICIENT. Because, B-A can be positive or negative
Note: Negative A-B or B-A will mean that the A-B or B-A will become B-A or A-B if either is negative.
COMBINED, we know X = A - B = B - A ; which means A=B=X=0. (Not sure if there is any other value?)
ANSWER: C.
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Is |X|= A-B?
1) X=A-B
2) X=B-A
As a general Rule of thumb, we know that | x| = x when x >=0 and | x| = - x when x < 0.
So, let's look at the 1st statement
X=A-B
We don't know whether A- B is +ve or -ve.
So, if A-B is +ve then X = A-B
if A- B is -ve then X = B-A
Now, let's look at the 2nd statement
X= B-A
if B-A is +ve then X = B-A
if B-A is -ve then X= A-B
So, individually neither of the statement can answer the question.
Now let's combine them....
So, X= A-B = B-A can only happen if A =B OR X= 0
which means |x| = 0 and A-B = 0
So, together they satisfy the main question or argument.
So, the answer is 'C'.
1) X=A-B
2) X=B-A
As a general Rule of thumb, we know that | x| = x when x >=0 and | x| = - x when x < 0.
So, let's look at the 1st statement
X=A-B
We don't know whether A- B is +ve or -ve.
So, if A-B is +ve then X = A-B
if A- B is -ve then X = B-A
Now, let's look at the 2nd statement
X= B-A
if B-A is +ve then X = B-A
if B-A is -ve then X= A-B
So, individually neither of the statement can answer the question.
Now let's combine them....
So, X= A-B = B-A can only happen if A =B OR X= 0
which means |x| = 0 and A-B = 0
So, together they satisfy the main question or argument.
So, the answer is 'C'.
Manoj K
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Statement 1:gmatusa2010 wrote:Is |X|= A-B?
1) X=A-B
2) X=B-A
If X = A-B = 1, then |X| = |1| = 1 and A-B = 1, so |X| = A-B.
If X = A-B = -1, then |X| = |-1| = 1 and A-B = -1, so |X| ≠A-B.
INSUFFICIENT.
Statement 2:
If X = B-A = 1, then |X| = |1| = 1 and A-B = -1, so |X| ≠A-B.
If X = B-A = -1, then |X| = |-1| = 1 and A-B = 1, so |X| = A-B.
INSUFFICIENT.
Statements combined:
Adding together X = A-B and X = B-A, we get:
X + X = (A-B) + (B-A)
2X = 0
X = 0.
Since X = A-B and X=0, A-B = 0.
Thus, |X| = A-B.
SUFFICIENT.
The correct answer is C.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
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