gmat prep - absolute x
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There are two cases in the main question stem
CASE 1
when x>0 implies is x=y-z?
CASE 2
When x<0 implies -x=y-z or is x+y=z
Now look at the two helps given (1) says x+y=z but it is not given if x<0 or not so INSUFFICIENT
(2) given x<o nothing about y and z so INSUFFICIENT
BOTH SUFFICIENT AS THEY SATISFY CASE2
CASE 1
when x>0 implies is x=y-z?
CASE 2
When x<0 implies -x=y-z or is x+y=z
Now look at the two helps given (1) says x+y=z but it is not given if x<0 or not so INSUFFICIENT
(2) given x<o nothing about y and z so INSUFFICIENT
BOTH SUFFICIENT AS THEY SATISFY CASE2
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IMO B
(1) x + y = z makes x = z - y, hence mod (x) = mod (z - y), which could be equal to y - z regardless what sign is x with, only if y > z. This is because an absolute value is non-negative; and since we know nothing about y and z, hence insufficient.
(2) reads x < 0, this means that z - y < 0; and this makes us believe that 'yes', mod (x) = y - z. So (2) alone is sufficient, hence B.
(1) x + y = z makes x = z - y, hence mod (x) = mod (z - y), which could be equal to y - z regardless what sign is x with, only if y > z. This is because an absolute value is non-negative; and since we know nothing about y and z, hence insufficient.
(2) reads x < 0, this means that z - y < 0; and this makes us believe that 'yes', mod (x) = y - z. So (2) alone is sufficient, hence B.
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
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State 2 not given any info regarding y and zsanju09 wrote:IMO B
(1) x + y = z makes x = z - y, hence mod (x) = mod (z - y), which could be equal to y - z regardless what sign is x with, only if y > z. This is because an absolute value is non-negative; and since we know nothing about y and z, hence insufficient.
(2) reads x < 0, this means that z - y < 0; and this makes us believe that 'yes', mod (x) = y - z. So (2) alone is sufficient, hence B.
not sufficient
It should be C.
- sanju09
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sanju09 wrote:IMO C
(1) x + y = z makes x = z - y, hence mod (x) = mod (z - y), which could be equal to y - z regardless what sign is x with, only if y > z. This is because an absolute value is non-negative; and since we know nothing about y and z, hence insufficient.
(2) reads x < 0, insufficient for the same reasons as given in (1).
(1) & (2) means that z - y < 0; and this makes us believe that 'yes', mod (x) = y - z, hence C.
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com