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Lines n and p lie in the xyplane. Is the slope of line n [#permalink]
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07 May 2006, 18:24
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Lines n and p lie in the xyplane. Is the slope of line n less than the slope of line p?
(1) Line n and p intersect at point (5,1)
(2) The y intercept of line n is greater than the y intercept of line p



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Re: DS: line n and p [#permalink]
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07 May 2006, 19:10
dinesh8 wrote: Lines n and p lie in the xyplane. Is the slope of line n less than the slope of line p? (1) Line n and p intersect at point (5,1) (2) The y intercept of line n is greater than the y intercept of line p
C?
1. alone doesnt give us much info, ie slope.
2. taking 2 alone still does surve the much.
taking both we know the common point, and since yint of n is greater its slope is always less steepler or more negaive. so C.



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I am getting E..
What is both the slopes are negative? The one with larger incercept will have a larger slope!
But in case both are positive, the one with smaller intercept will have larger slope.



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sm176811 wrote: I am getting E..
What is both the slopes are negative? The one with larger incercept will have a larger slope!
But in case both are positive, the one with smaller intercept will have larger slope.
if both r negative, the one with larger yint will have a larger negative slope. If a slope is more more negative, wouldn't that make it smaller? I know from a steepness point of view its not true. Please correct me, as I am little unsure. thanks



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Yeah, more ve is smaller
Any number (in the negative range), the more netaive it is, the smaller it is!



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sm176811 wrote: Yeah, more ve is smaller
Any number (in the negative range), the more netaive it is, the smaller it is!
Thanks, so n will always have a smaller slope then p, therefore C. rite?



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shampoo wrote: sm176811 wrote: Yeah, more ve is smaller
Any number (in the negative range), the more netaive it is, the smaller it is! Thanks, so n will always have a smaller slope then p, therefore C. rite?
Well for both +ve, n is smaller, both ve n is larger!



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sm176811 wrote: shampoo wrote: sm176811 wrote: Yeah, more ve is smaller
Any number (in the negative range), the more netaive it is, the smaller it is! Thanks, so n will always have a smaller slope then p, therefore C. rite? Well for both +ve, n is smaller, both ve n is larger!
I disagree, I think n will always be smaller, since the yint is lesser.



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shampoo wrote: sm176811 wrote: shampoo wrote: sm176811 wrote: Yeah, more ve is smaller
Any number (in the negative range), the more netaive it is, the smaller it is! Thanks, so n will always have a smaller slope then p, therefore C. rite? Well for both +ve, n is smaller, both ve n is larger! I disagree, I think n will always be smaller, since the yint is lesser.
Then again when I think abut that slope=steepness of a line in that case the answer should be E.



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Anyone else wanna comment on this?
What is the OA?



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Joined: 01 May 2006
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I think it's (C)
1) giving y = a(p)*x + b(p) and y = a(n)*x + b(n)
we have :
1= 5*a(p) + b(p)
1= 5*a(n) + b(n)
Not sufficient
2) is b(n) > b(p)
combining (1) and (2)
we have : 15*a(n) > 15*a(p)
which means : a(n) < a(p)



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Joined: 03 May 2006
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Let N be : y= m1x+ c1
Let P be : y= m2x + c2
From 1st stmt, 1 = 5m1 + c1 ; 1 = 5m2 + c2
Hence, m1m2 = (c2c1)/5.
Insuff since we don't know the reln between c1 and c2.
From 2nd stmt, c1>c2. Insuff.
Combining, m1  m2 < 0 > m1 < m2
Hence, (C).



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it have to be C.
Since they intersect on the 1st quadrant. One is rising faster than the other one.



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Joined: 04 May 2006
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The OA is C  I got this question on the GMATPrep test.
It still puzzles me a bit, though  I also think about that option when the yintercepts of n and p are both positive.
Lets take point (0,4) as yintersept of n, and point (0,3) as yintersept of p
The slope of n is 41/05=3/5=0.6
The slope of p is 31/05=2/5=0.4
BUT 0.6>0.4 IS NOT TRUE!!!
Can someone figure out this discrepancy and explain it in terms of real numbers, not formulas?
Thanks a lot in advance!



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luxmaria wrote: The OA is C  I got this question on the GMATPrep test.
It still puzzles me a bit, though  I also think about that option when the yintercepts of n and p are both positive.
Lets take point (0,4) as yintersept of n, and point (0,3) as yintersept of p
The slope of n is 41/05=3/5=0.6
The slope of p is 31/05=2/5=0.4
BUT 0.6>0.4 IS NOT TRUE!!!
Can someone figure out this discrepancy and explain it in terms of real numbers, not formulas?
Thanks a lot in advance!
The questions asks "Is the slope of line n less than the slope of line p?"
Based on your number, 0.6 IS smaller than 0.4, so the answer is YES, C is sufficient
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Thank you TeHCM!
How could I not see that?



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still no OA
IMO E
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Joined: 06 May 2006
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Has to be C.
This is one of the questions that you would get in a flash if you drew a rough diagram










