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In the figure above, if angle ABC = 110 degrees, and angle AED = 100 d [#permalink]
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23 Jun 2011, 14:31
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In the figure above, if angle ABC = 110 degrees, and angle AED = 100 degrees, then angle ADE is how many degrees smaller than angle BCD? (1) Angle DAB = 45 degrees (2) Angle ADC + angle BCD = 205 degrees Hello. I am doing the PR1012, and I came across this question. I got it wrong to begin with, but I also do not understand their brief explanation. Please help me. Just for the record I am in the college class of 2015, but I need to take the GMAT before the end of my sophomore year for a combined degree program (shooting for 700; I know it is really hard!). Eventually I may want an MBA, though. I am studying now to ease into it. I am pretty smart for the most part, but I do badly on tests. I got a 1380 SAT (670M, 710CR) with a little studying. Anyway, here is the question. After one day of studying I already hate the data questions. In the figure above, if angle ABC = 110 degrees, and angle AED = 100 degrees, then angle ADE is how many degrees smaller than angle BCD? 1. Angle DAB = 45 degrees 2. Angle ADC + angle BCD = 205 degrees OPEN DISCUSSION OF THIS QUESTION IS HERE: thisdsijustcannotfigureoutiamgettinge99063.html== Message from GMAT Club Team == This is not a quality discussion. It has been retired. If you would like to discuss this question please repost it in the respective forum. Thank you! To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative  Verbal Please note  we may remove posts that do not follow our posting guidelines. Thank you.
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Last edited by jw on 23 Jun 2011, 20:27, edited 1 time in total.



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Re: In the figure above, if angle ABC = 110 degrees, and angle AED = 100 d [#permalink]
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23 Jun 2011, 15:10
st2 is fairly simple to get BCD  ADE, so st is sufficient.
as per st 1, BCD = 36011010045DAE BCD = 105DAE
for triangle ADE, DAE = 180100ADE DAE = 80ADE
combining both eqns, BCD = 10580+ADE ==> BCD  ADE = 25 sufficient.



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Re: In the figure above, if angle ABC = 110 degrees, and angle AED = 100 d [#permalink]
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23 Jun 2011, 22:47
My apologies for misposting.
Please move this to the data sufficiency forum.



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Re: In the figure above, if angle ABC = 110 degrees, and angle AED = 100 d [#permalink]
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24 Jun 2011, 13:28
St 2 is very simple, as discussed in the above post. But I solved the first stmt like below, I hope it'll help you! Let <BCD = y; <ADE = x; therefore <CDA = 180  x (since, <CDA and <ADE are supplimentary)
Now sum of angles of quadrilateral ABCD is 360; <DAB + <ABC + <BCD + <CDA = 360 => 45 + 110 + Y + 180  X = 360
You can get the difference b/t y and X which is the answer for the question. Therefore the answer is D



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Re: In the figure above, if angle ABC = 110 degrees, and angle AED = 100 d [#permalink]
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24 Jun 2011, 14:39
I still do not see how statement two is so simple.



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Re: In the figure above, if angle ABC = 110 degrees, and angle AED = 100 d [#permalink]
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24 Jun 2011, 14:50
jw wrote: I still do not see how statement two is so simple. Sum of angles in a straight line is 180. ADE+ADC=180 ADC=180ADE 1 2. ADC + BCD = 205 Substitute ADC from 1 180ADE+BCD=205 BCDADE=205180=25 BCDADE is nothing but the difference asked in the question stem. Sufficient.
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Re: In the figure above, if angle ABC = 110 degrees, and angle AED = 100 d [#permalink]
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14 Aug 2017, 03:18
jw wrote: In the figure above, if angle ABC = 110 degrees, and angle AED = 100 degrees, then angle ADE is how many degrees smaller than angle BCD? (1) Angle DAB = 45 degrees (2) Angle ADC + angle BCD = 205 degrees Hello. I am doing the PR1012, and I came across this question. I got it wrong to begin with, but I also do not understand their brief explanation. Please help me. Just for the record I am in the college class of 2015, but I need to take the GMAT before the end of my sophomore year for a combined degree program (shooting for 700; I know it is really hard!). Eventually I may want an MBA, though. I am studying now to ease into it. I am pretty smart for the most part, but I do badly on tests. I got a 1380 SAT (670M, 710CR) with a little studying. Anyway, here is the question. After one day of studying I already hate the data questions. In the figure above, if angle ABC = 110 degrees, and angle AED = 100 degrees, then angle ADE is how many degrees smaller than angle BCD? 1. Angle DAB = 45 degrees 2. Angle ADC + angle BCD = 205 degrees Important property of polygons: Sum of Interior Angles of a polygon is \(180(n2)\) where \(n\) is the number of sides. So for quadrilateral sum of the angles equals to \(180(42)=360\) degrees. Given: \(\angle{ABC}=110\) and \(\angle{AED}=100\). Question: \(\angle{BCD}\angle{ADE}=?\). Attachment: DS.jpg Now as \(\angle{ABC}=110\) and \(\angle{AED}=100\) and the sum of all angles is 360 degrees then the sum of other two angles in quadrilateral must be \(\angle{BCD}+\angle{BAE}=360(110+100)=150\). (1) \(\angle{DAB}=45\) > \(\angle{BAE}=\angle{DAB}+\angle{DAE}=45+\angle{DAE}\), but \(\angle{DAE}=180100\angle{ADE}=80\angle{ADE}\) (the sum of interior angles in triangle ADE equals to 180 degrees) > \(\angle{BAE}=45+80\angle{ADE}=125\angle{ADE}\). So \(\angle{BCD}+\angle{BAE}=150\) becomes \(\angle{BCD}+125\angle{ADE}=150\) > \(\angle{BCD}\angle{ADE}=25\). Sufficient. (2) \(\angle{BCD}+\angle{ADC}=205\) > \(\angle{ADC}=180\angle{ADE}\) (straight line) > \(\angle{BCD}+180\angle{ADE}=205\) > \(\angle{BCD}\angle{ADE}=25\). Sufficient. Answer: D. OPEN DISCUSSION OF THIS QUESTION IS HERE: thisdsijustcannotfigureoutiamgettinge99063.html== Message from GMAT Club Team == This is not a quality discussion. It has been retired. If you would like to discuss this question please repost it in the respective forum. Thank you! To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative  Verbal Please note  we may remove posts that do not follow our posting guidelines. Thank you.
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Re: In the figure above, if angle ABC = 110 degrees, and angle AED = 100 d
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