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If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ?
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Updated on: 10 Sep 2015, 09:33
Question Stats:
90% (01:40) correct 10% (02:07) wrong based on 61 sessions
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If \(x^a = 2\), \(x^b = 3\) and\(x^c = 6\) then \(x^{(3a+b2c)} =\) ? A) 1/9 B) 1/6 C) 1/2 D) 2/3 E) 3/4 It's meant to read x^(3a+b2c) = ? Is this a valid question? I had no idea where to start?
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Originally posted by skylimit on 10 Sep 2015, 09:27.
Last edited by Bunuel on 10 Sep 2015, 09:33, edited 2 times in total.
Renamed the topic and edited the question.



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If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ?
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Updated on: 10 Sep 2015, 10:00
Question Stem can be re  written as
[X^(3a) * X^(b)] / [ X^(2c)]
Now Substitute the respective values fron the stem i.e (X^a) = 2, (X^b) = 3 & (X^ c) = 6.
[2^3 * 3] / 6^2 = 2 / 3.
Therefore Ans is D.



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Re: If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ?
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10 Sep 2015, 09:54
goldfinchmonster wrote: Question Stem can be re  written as
[X^(3a) * X^(b)] / [ X^(2c)]
Now Substitute the respective values fron the stem i.e (X^a) = 2, (X^b) = 3 & (X^ c) = 6.
[2^3 * 3] / 6^2 = 2 / 3.
Therefore Ans is D. I understood the answer that was with the question, but is it a valid question? Would I ever see such a question on the real test?



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If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ?
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10 Sep 2015, 10:05
Hi
Though i am not the right person to answer your query, but according to me this question can very well be a part of GMAT. It just tests basic exponent rules.
It would be nice if bunuel could put some light on this query.



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Re: If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ?
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10 Sep 2015, 10:34
goldfinchmonster wrote: Hi
Though i am not the right person to answer your query, but according to me this question can very well be a part of GMAT. It just tests basic exponent rules.
It would be nice if bunuel could put some light on this query. This is a pretty regular question for GMAT standards as it tests addition and subtration of exponents with same bases.



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Re: If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ?
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01 Aug 2018, 09:03
I dont really understand this question, could someone elaborate?
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A couple of things that helped me in verbal: https://gmatclub.com/forum/verbalstrategies268700.html#p2082192
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If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ?
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01 Aug 2018, 09:15
Arro44Using the formula \(x^{a+b+c} = x^a * x^b * x^c\) GIven equation \(x^{3a+b2c}\) can be rewritten as \(x^{3a}*x^b*x^{2c}\) It involves 3 terms \(x^{3a}\) and \(x^b\) and \(x^{2c}\) If we can find the values of above 3 independent terms, we can find the value of the total term Using the formula \((x^a)^b = x^{ab}\) We need to find \(x^{3a}\) => \((x^a)^3\) = \(2^3 = 8\) We already have \(x^b = 3\) \(x^{2c}\) = \((x^c)^{2}\) = \(6^{2}\) = \(\frac{1}{36}\) The product of all the terms = \(\frac{8*3}{36} = \frac{2}{3}\) Hence option D
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If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ?
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01 Aug 2018, 09:20
workout wrote: Arro44Using the formula \((x^a)^b = x^{ab}\) We need to find \(x^{3a}\) => \((x^a)^3\) = \(2^3 = 8\) We already have \(x^b = 3\) Hence option D This is where I got lost... How come we now take some to the power of something else and then get 2? EDIT: Its cause it was mentioned in the question stem, now I get it Thank you!
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A couple of things that helped me in verbal: https://gmatclub.com/forum/verbalstrategies268700.html#p2082192
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If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ?
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01 Aug 2018, 09:22
Arro44 wrote: workout wrote: Arro44Using the formula \((x^a)^b = x^{ab}\) We need to find \(x^{3a}\) => \((x^a)^3\) = \(2^3 = 8\) We already have \(x^b = 3\) Hence option D This is where I got lost... How come we now take some to the power of something else and then get 2? This information is provided in the question stem \(x^a = 2\) and \(x^b = 3\) and \(x^c = 6\)
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If x^a = 2, x^b = 3 and x^c = 6 then x^(3a + b  2c) = ? &nbs
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