If p, q, r, and s are consecutive integers, with p<q<r<s, is pr<qs?
(1) pq<rs
(2) ps<qr
Guys ,
Cant we do this question be letting p=1&-1 , q=2&-2 , r=3&-3 , s=4&-4 ?
Pls suggest me..
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p,q,r,s consecutive no.
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j_shreyans
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Hi j_shreyans,
This DS question requires that P<Q<R<S AND that the variables be consecutive integers. There are lots of groups of numbers to choose from. We could use:
All positives
P=1
Q=2
R=3
S=4
All negatives
P=-4
Q=-3
R=-2
S=-1
A "mix"
P=-2
Q=-1
R=0
S=1
To address your original question, if P = -1, then the negative values that you chose for the other variables are INCORRECT. P has to be the smallest number (so Q, R and S have to be GREATER than -1)
With that note, you should re-try this question. If you're still unsure of what to do, then post back here and I'll walk you through it.
GMAT assassins aren't born, they're made,
Rich
This DS question requires that P<Q<R<S AND that the variables be consecutive integers. There are lots of groups of numbers to choose from. We could use:
All positives
P=1
Q=2
R=3
S=4
All negatives
P=-4
Q=-3
R=-2
S=-1
A "mix"
P=-2
Q=-1
R=0
S=1
To address your original question, if P = -1, then the negative values that you chose for the other variables are INCORRECT. P has to be the smallest number (so Q, R and S have to be GREATER than -1)
With that note, you should re-try this question. If you're still unsure of what to do, then post back here and I'll walk you through it.
GMAT assassins aren't born, they're made,
Rich
Rich,
Using your numbers for example:
Statement 1: pq<rs
(1)(2)<(3)(4)--> 2<12 TRUE
(-4)(-3)<(-2)(-1)--> 12<2 FALSE
(-2)(-1)<(0)(1)--> 2<0 FALSE
Statement 1 alone is sufficient.
Statement 2: ps<qr
(1)(4)<(2)(3)--> 4<6 TRUE
(-4)(-1)<(-3)(-2)--> 4<6 TRUE
(-2)(1)<(-1)(0)--> -2<0 TRUE
Statement 2 alone is not sufficient.
Knowing that your integers must be all positives and consecutive, one can reason that pr<qs
ANSWER:
(A)Statement 1 alone is sufficient, but statement 2 alone is not sufficient to answer the question[/u]
Using your numbers for example:
Statement 1: pq<rs
(1)(2)<(3)(4)--> 2<12 TRUE
(-4)(-3)<(-2)(-1)--> 12<2 FALSE
(-2)(-1)<(0)(1)--> 2<0 FALSE
Statement 1 alone is sufficient.
Statement 2: ps<qr
(1)(4)<(2)(3)--> 4<6 TRUE
(-4)(-1)<(-3)(-2)--> 4<6 TRUE
(-2)(1)<(-1)(0)--> -2<0 TRUE
Statement 2 alone is not sufficient.
Knowing that your integers must be all positives and consecutive, one can reason that pr<qs
ANSWER:
(A)Statement 1 alone is sufficient, but statement 2 alone is not sufficient to answer the question[/u]
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Hi pfg2181,
The examples that I offered to j_shreyans were meant to point out a small mistake in her thinking (and to encourage a thorough set of TESTs); they are not a complete set in-and-of themselvesl On certain questions, you would have to do MORE work to be sure that you had gotten the correct answer. That having been said, your answer is correct, but I do want to point out one small mistake in your thinking:
In Fact 1, the 4 values do NOT need to all be positive. You could use the following set of values:
P=-1
Q=0
R=1
S=2
These values "fit" all of the given information (including the info in Fact 1) and would also lead to a YES answer.
GMAT assassins aren't born, they're made,
Rich
The examples that I offered to j_shreyans were meant to point out a small mistake in her thinking (and to encourage a thorough set of TESTs); they are not a complete set in-and-of themselvesl On certain questions, you would have to do MORE work to be sure that you had gotten the correct answer. That having been said, your answer is correct, but I do want to point out one small mistake in your thinking:
In Fact 1, the 4 values do NOT need to all be positive. You could use the following set of values:
P=-1
Q=0
R=1
S=2
These values "fit" all of the given information (including the info in Fact 1) and would also lead to a YES answer.
GMAT assassins aren't born, they're made,
Rich
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j_shreyans
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Hi Rich ,
I have tested the question will all possible values but didn't come to any conclusion.
for e.g. p=-1 , q=0 , r=1 , s=2
TARGET = pr<qs
statement 1 - pq<rs
(-1)(0)<(1)(2)
0<2 which is true
Now put this value in our target
pr<qs
(-1)(1)<(0)(2)
-1<0 satisfy
Statement 2 - ps<qr
(-1)(2)<(0)(1)
-2<0 - true
Now Target pr<qs
(-1)(1)<(0)(2)
-1<0 also sufficient.
I know i am wrong pls correct me .
I have put lots of time in this question but......uuufffff
OA is A
I have tested the question will all possible values but didn't come to any conclusion.
for e.g. p=-1 , q=0 , r=1 , s=2
TARGET = pr<qs
statement 1 - pq<rs
(-1)(0)<(1)(2)
0<2 which is true
Now put this value in our target
pr<qs
(-1)(1)<(0)(2)
-1<0 satisfy
Statement 2 - ps<qr
(-1)(2)<(0)(1)
-2<0 - true
Now Target pr<qs
(-1)(1)<(0)(2)
-1<0 also sufficient.
I know i am wrong pls correct me .
I have put lots of time in this question but......uuufffff
OA is A
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j_shreyans
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Matt@VeritasPrep
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Why not approach it this way:
p = p
q = p + 1
r = p + 2
s = p + 3
We want to know if p * (p + 2) < (p + 1) * (p + 3), which reduces to p² + 2p < p² + 4p + 3, or 0 < 2p + 3, or -3/2 < p. So the real question is "Is p > -3/2?"
S1 gives us p * (p + 1) < (p + 2) * (p + 3), which reduces to p² + p < p² + 5p + 6, or 0 < 4p + 6, or 0 < 2p + 3, or -3/2 < p. Success! SUFFICIENT
S2 gives us p * (p + 3) < (p + 1) * (p + 2), which reduces to p² + 3p < p² + 3p + 2, or 0 < 2. Not very helpful, obviously!
p = p
q = p + 1
r = p + 2
s = p + 3
We want to know if p * (p + 2) < (p + 1) * (p + 3), which reduces to p² + 2p < p² + 4p + 3, or 0 < 2p + 3, or -3/2 < p. So the real question is "Is p > -3/2?"
S1 gives us p * (p + 1) < (p + 2) * (p + 3), which reduces to p² + p < p² + 5p + 6, or 0 < 4p + 6, or 0 < 2p + 3, or -3/2 < p. Success! SUFFICIENT
S2 gives us p * (p + 3) < (p + 1) * (p + 2), which reduces to p² + 3p < p² + 3p + 2, or 0 < 2. Not very helpful, obviously!
