OG 13 PS 211

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OG 13 PS 211

by bpolley00 » Fri Apr 26, 2013 10:09 am
OK I have a huge issue with this question, so experts please correct me if I am wrong. The answer explains that the line passes through 0,2 and 3,0. How do you know this based on the diagram? the diagram also does not say the graph is of scale. This information isn't listed anywhere, so now we are just supposed to assume the points on this question in which it crosses the X axis and Y axis?
The best way I know how to look at it is you know the line has a negative slope so you can immediately cross off every answer except for B and C.
Don't you think that this questions is quite presumptuous? Either I am missing something here or they made an error in my specific OG book; which, I don't think is the issue.

-BP
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by Anju@Gurome » Fri Apr 26, 2013 10:22 am
bpolley00 wrote:OK I have a huge issue with this question, so experts please correct me if I am wrong. The answer explains that the line passes through 0,2 and 3,0. How do you know this based on the diagram? the diagram also does not say the graph is of scale. This information isn't listed anywhere, so now we are just supposed to assume the points on this question in which it crosses the X axis and Y axis?
Image
Note that two 1s are marked on the coordinate axes, one in x-axis and the other in y-axis, and there are tick marks on the axes too. This means distance between two consecutive tick marks is 1.

Now, the line crosses x-axis at 3 units distance from origin ---> the line crosses x-axis at (3, 0)
And, the line crosses y-axis at 2 units distance from origin ---> the line crosses y-axis at (0, 2)

It's true that the problem never said that the figure is drawn to scale but at the beginning of the practice questions, the directions for solving the problems clearly says :
Figures: A figure accompanying a problem solving question is intended to provide information
useful in solving the problem. Figures are drawn as accurately as possible. Exceptions will be clearly noted. Lines shown as straight are straight, and lines that appear jagged are also straight. The positions of points, angles, regions, etc., exist in the order shown, and angle measures are greater than zero. All figures lie in a plane unless otherwise indicated.
Which means the figures are drawn to scale; when it is not drawn to scale, they will mention that the figure is not drawn to scale.
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by GMATGuruNY » Fri Apr 26, 2013 10:26 am
bpolley00 wrote:OK I have a huge issue with this question, so experts please correct me if I am wrong. The answer explains that the line passes through 0,2 and 3,0. How do you know this based on the diagram? the diagram also does not say the graph is of scale. This information isn't listed anywhere, so now we are just supposed to assume the points on this question in which it crosses the X axis and Y axis?
The best way I know how to look at it is you know the line has a negative slope so you can immediately cross off every answer except for B and C.
Don't you think that this questions is quite presumptuous? Either I am missing something here or they made an error in my specific OG book; which, I don't think is the issue.

-BP
Image

From the introduction to the PS section in the OG:
A figure accompanying a problem solving question is intended to provide information useful in solving the problem. Figures are drawn as accurately as possible. Exceptions will be clearly noted. Lines shown as straight are straight, and lines that appear jagged are also straight. The positions of points, angles, regions, etc., exist in the order shown, and angle measures are greater than zero. All figures lie in a plane unless otherwise indicated.

In the problem above, you have already noted that only B and C offer lines with a negative slope.
Answer choice C: 3x+2y = 6.
Here, if y=0, then x=2, implying that the x-intercept is (2,0).
In the figure, the x-intercept is clearly greater than 2.
Eliminate C.

The correct answer is B.
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by bpolley00 » Fri Apr 26, 2013 10:35 am
Ha, thanks for both responses. To address the first response- but there isn't a third tick mark, so you would be making an assumtion that the tick market and where the line crossing is exactly equal, right? Theoretically speaking, you have no way of knowing that. It could be slightly larger or slightly smaller.

Mitch- ok I admit it, you got me :). The plugging in numbers after the assumption that the line has a negative slope works as you can clearly see that the line cannot land on the X axis at 0,2. That is such a darn nuance.

I am not happy with the 650, so I am literally re-going through every single question. If I am going to apply to a top business school I want to do it the right way and earn it, not just squeeze in. Thanks for the explanations.

-BP

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by bpolley00 » Fri Apr 26, 2013 10:42 am
Also,

If what I just posted is correct, don't you think GMAC should consider revising the way the answer is explained. :X