Is |p| = q - r?
(1) p + q = r.
(2) p < 0.
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Is |p| =
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sanju09
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raviki8208
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using 1 alone,sanju09 wrote:Is |p| = q - r?
(1) p + q = r.
(2) p < 0.
p = r - q so not sufficient
using 2 alone,
p r q relation is not known.
uisng both
if p < 0, |p| = -p so,
|p| ≠q - r so, sufficient .. Answer is C
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sk818020
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(1) p+q=r, rewritten is;
p=q-r
Both side have to be positive or negative. It can't be that both sides have opposite signs. Thus,
If q-r is negative, lpl does not equal q-r.
If q-r is postive, then lpl=q-r.
Thus, (1) insufficient.
(2) p<0. This doesn't say anything about q or r. Thus, (2) insufficent.
Put them together, because p<0, q-r must also be negative. Thus lpl does not equal q-r. Thus,
IMO the answer is C.
What is the OA?
p=q-r
Both side have to be positive or negative. It can't be that both sides have opposite signs. Thus,
If q-r is negative, lpl does not equal q-r.
If q-r is postive, then lpl=q-r.
Thus, (1) insufficient.
(2) p<0. This doesn't say anything about q or r. Thus, (2) insufficent.
Put them together, because p<0, q-r must also be negative. Thus lpl does not equal q-r. Thus,
IMO the answer is C.
What is the OA?
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November Rain
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IMO A
If |p| = q - r it means that either p = q - r or (-p) = q - r
Statement 1 tell us that p + q = r -> p = r - q -> - p = q - r
Sufficient.
Statment B does not tell us anything. Insufficient
If |p| = q - r it means that either p = q - r or (-p) = q - r
Statement 1 tell us that p + q = r -> p = r - q -> - p = q - r
Sufficient.
Statment B does not tell us anything. Insufficient
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sk818020
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(1) is not sufficient because what if r-q is negative? It couldn't possibly be equal lpl. (1) does not tell us that r-q is not negative. It tells us it is equal to p. P could be negative. Therefore, r-q could be negative, at which point r-q could not equal an absolute value because absolute values are always positive.November Rain wrote:IMO A
If |p| = q - r it means that either p = q - r or (-p) = q - r
Statement 1 tell us that p + q = r -> p = r - q -> - p = q - r
Sufficient.
Statment B does not tell us anything. Insufficient
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thinkpanther
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IMO C
1) p + q = r
p = r-q
by definition of absolute value
when p is +ve |p| = p and when p is -ve |p| = -p
so insufficient
2) p <0 insufficient
combined:
|p| = -p = q-r hence sufficient
1) p + q = r
p = r-q
by definition of absolute value
when p is +ve |p| = p and when p is -ve |p| = -p
so insufficient
2) p <0 insufficient
combined:
|p| = -p = q-r hence sufficient
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November Rain
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Yes, you're right. I missed that possibility.IMO A
If |p| = q - r it means that either p = q - r or (-p) = q - r
Statement 1 tell us that p + q = r -> p = r - q -> - p = q - r
Sufficient.
Statment B does not tell us anything. Insufficient
(1) is not sufficient because what if r-q is negative? It couldn't possibly be equal lpl. (1) does not tell us that r-q is not negative. It tells us it is equal to p. P could be negative. Therefore, r-q could be negative, at which point r-q could not equal an absolute value because absolute values are always positive.
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nikhilkatira
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sanju09
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nikhilkatira wrote:What is the OA ?
When each statement alone is not clicking, we then take p = r - q, which is negative, cannot equal an absolute value; but q - r could.
[spoiler]C the OA[/spoiler]
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
