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If (x + y)/(xy) = 1, then y = [#permalink]
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05 Mar 2014, 02:09
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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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05 Mar 2014, 02:09




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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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05 Mar 2014, 19:34
\(Answer = A = \frac{x}{(x  1)}\) \(\frac{(x + y)}{(xy)} = 1\) x + y = xy xy  y = x y(x1) = x \(y = \frac{x}{(x1)}\)
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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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05 Mar 2014, 21:08
(x + y)/(xy) = 1 (x/xy) + (y/xy) = 1 1/y + 1/x = 1 1/y = 1  1/x 1/y = (x1)/x => y = x/(x1)
Ans is (A).



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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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10 Feb 2015, 02:02
Bunuel wrote: SOLUTION
If (x + y)/(xy) = 1, then y =
(A) x/(x  1) (B) x/(x + 1) (C) (x  1)/x (D) (x + 1)/x (E) x
\(\frac{x + y}{xy} = 1\);
\(x + y = xy\);
\(x = xyy\);
\(x = y(x1)\);
\(y=\frac{x}{x1}\).
Answer: A. Could you please explain the last step ? i.e. how you got from x= y(x1) to your solution?! Yo divided x by y and then you got x/y=(x1) and how do you get the x over now ?



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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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10 Feb 2015, 05:55



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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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11 Feb 2015, 07:15
Thanks a lot  after 5/6 hours i sometimes get a little bit confused with the easiest calculations.
Sorry



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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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22 Nov 2015, 10:54
I had a very strange way of solving this. Might not always work.
I plugged in numbers and already wasted enough time trying to figure out which numbers to plug in that I didn't want to go back and solve algebraically.
So what numbers added to each other and divided by the product of each other equals 1? The only ones I could think of included 0 making the solution undefined. X=1 Y=0 ...... Answer A is also Undefined while all the others give some sort of solution.
Warning: I suck at math so take my advice with a grain of salt.



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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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25 Nov 2015, 15:45
Hi DJ1986, This question is a type of 'in terms of' question  the prompt gives you an equation and asks you to isolate one of the variables 'in terms of' the other variable(s) in the equation. These types of questions are typically best solved with Algebra (TESTing VALUES can get complicated and you might not easily find values that 'fit' the given equation. To answer your question though, X=2, Y=2 gives us (2+2)/(2)(2) = 1. Using those values would lead us to 2 answers though (Answers A and E). GMAT assassins aren't born, they're made Rich
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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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22 May 2017, 18:39
Quote: If (x + y)/(xy) = 1, then y =
(A) x/(x  1) (B) x/(x + 1) (C) (x  1)/x (D) (x + 1)/x (E) x
We can simplify the given equation: (x + y)/(xy) = 1 x + y = xy x = xy  y x = y(x  1) x/(x  1) = y Answer: A
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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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10 Oct 2017, 08:03
I was wondering if you guys could help me with my timing issue. I've attached a picture of how I approach the simplification of this problem. A s you can see, I only got it right from the 3rd time. The first 2 attempts, in which I tried to immediately isolate y on the RHS, wasted quite a bit of my time. I'm wondering is there an approach that I'm missing? Is there a way I can see from the problem that I shouldn't be isolating y straight away? Thank you for your help!
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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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27 Feb 2018, 09:40
Bunuel wrote: SOLUTION
If (x + y)/(xy) = 1, then y =
(A) x/(x  1) (B) x/(x + 1) (C) (x  1)/x (D) (x + 1)/x (E) x
\(\frac{x + y}{xy} = 1\);
\(x + y = xy\);
\(x = xyy\);
\(x = y(x1)\);
\(y=\frac{x}{x1}\).
Answer: A. Bunuel  how did you get "1" here \(x = y(x1)\); Also i wonder why my solution is not correct, pls see below \(\frac{x + y}{xy} = 1\); x+y =xy xy=x+y x = \(\frac{x+y}{x}\)



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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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27 Feb 2018, 10:34



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Re: If (x + y)/(xy) = 1, then y = [#permalink]
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28 Feb 2018, 01:37
Bunuel wrote: The Official Guide For GMAT® Quantitative Review, 2ND EditionIf (x + y)/(xy) = 1, then y = (A) x/(x  1) (B) x/(x + 1) (C) (x  1)/x (D) (x + 1)/x (E) x Problem Solving Question: 128 Category: Algebra Firstdegree equations Page: 78 Difficulty: 600 GMAT Club is introducing a new project: The Official Guide For GMAT® Quantitative Review, 2ND Edition  Quantitative Questions ProjectEach week we'll be posting several questions from The Official Guide For GMAT® Quantitative Review, 2ND Edition and then after couple of days we'll provide Official Answer (OA) to them along with a slution. We'll be glad if you participate in development of this project: 1. Please provide your solutions to the questions; 2. Please vote for the best solutions by pressing Kudos button; 3. Please vote for the questions themselves by pressing Kudos button; 4. Please share your views on difficulty level of the questions, so that we have most precise evaluation. Thank you! IMO A I am not so good in algebra so going through plugin we can write x+y=xy this can be possible through x=2 and y=2 or x=0 and y=0 so A ill give me the required result.




Re: If (x + y)/(xy) = 1, then y =
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