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DS question : not very clear

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DS question : not very clear

by ankitbagla » Sun Oct 20, 2013 4:26 am
In the figure to the left, the rectangle with side AE represents a flat roof on which is mounted a solar panel. The line segments AB and CD represent the panel, in two of its possible positions. How much longer is DE than BE ?

(1) CD is 24 meters long.

(2) BE is 12 meters long.
Source : Grockit
In the solution they have mentioned that hypotenuse to be same . How can we assume hypotenuse to be same ? So landed up to answer C but answer is DImage
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Last edited by ankitbagla on Sun Oct 20, 2013 4:36 am, edited 1 time in total.
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by mevicks » Sun Oct 20, 2013 4:31 am
ankitbagla wrote:In the figure to the left, ...
I think you need to attach an image for this one. Use https://myimgur.eden.fm/ or similar to post the image screenshot.
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by mevicks » Sun Oct 20, 2013 4:49 am
ankitbagla wrote: Image

In the figure to the left, the rectangle with side AE represents a flat roof on which is mounted a solar panel. The line segments AB and CD represent the panel, in two of its possible positions. How much longer is DE than BE ?

(1) CD is 24 meters long.
(2) BE is 12 meters long.
Q: We need the values of DE, DB & BE
Note that CD = AB
(it would be easier to think if you consider that its a ladder and not a solar panel)

St1: CD = 24 (The length of the solar panel is given)
AB = 24
We know the Hypotenuse of the 30-60-90 & 45-45-90 triangle, thus we can find length of all the sides.
SUFFICIENT

St2: BE = 12
We know one side of the 30-60-90 triangle, thus we can find its Hypotenuse. Corresponding to this value of the Hypotenuse we can find the lengths for the 45-45-90 triangle
SUFFICIENT

Answer D
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by theCodeToGMAT » Sun Oct 20, 2013 4:49 am
Answer {D}
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by theCodeToGMAT » Sun Oct 20, 2013 4:54 am
Key to this question is the knowledge to 30-60-90 & 45-45-90 Triangle.
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by [email protected] » Sun Oct 20, 2013 1:35 pm
Hi ankitbagla,

GMAT questions are specifically worded to provide you with information. If you're reading too fast or not taking notes, you might miss a small (but important) piece of information.

Here, we're told that AB and CD are the SAME PANEL, in 2 positions. That's how we know that the 2 lengths are equal. With THAT information, the rest of the question comes down to a set of standard geometry formulas.

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Rich
Contact Rich at [email protected]
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