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Medium-level root/exponent question

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Source: — Problem Solving |

by cramya » Tue Dec 16, 2008 5:34 pm
x^1/6 = 6

(x^1/6)^6 = 6^6

x = 6^6

sqrt((6^6)^6)

sqrt(6^36) = 6^18

D)
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by cramya » Tue Dec 16, 2008 5:36 pm
Brent,
Keep up the good work of posting quality questions. I have seen a few other questions that u posted also and they are good.

Regards,
Cramya
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by Brent@GMATPrepNow » Tue Dec 16, 2008 5:45 pm
Thanks Cramya
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by brb588 » Tue Dec 16, 2008 6:28 pm
Yeah, you post some good stuff. I hate to see that this is only medium difficulty, as I was a little shaky how to figure it out, but I got it! :)
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Re: Medium-level root/exponent question

by logitech » Tue Dec 16, 2008 7:34 pm
X^(6/2)/X^(1/6) = ANSWER/6

Answer : 6^18
LGTCH
---------------------
"DON'T LET ANYONE STEAL YOUR DREAM!"
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by Brent@GMATPrepNow » Tue Dec 16, 2008 8:37 pm
Maybe I should take back that part about "medium difficulty." I was distinguishing this question from super hard 700+ level questions.

I'd say that this question would rank in the 600-650 range.
Anyone else agree with that?
Brent Hanneson - Creator of GMATPrepNow.com
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by cramya » Tue Dec 16, 2008 9:22 pm
Anyone else agree with that?
Woudnt doubt an online GMAT instructor :-)
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by brb588 » Tue Dec 16, 2008 9:39 pm
Brent Hanneson wrote:I'd say that this question would rank in the 600-650 range.
Anyone else agree with that?
Well, in testing, I'm right at about 650, so I'll accept that. Thanks!
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by vittalgmat » Wed Dec 17, 2008 1:34 am
x^1/6 = 6
what is the value of x ^(6*1/2) ie x^3 ?

Dividing 3 by 1/6 we get 18.
So RHS should be raised to the power of 18.


I am guessing this is a 600 level problem.

thanks
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by vittalgmat » Wed Dec 17, 2008 1:35 am
Brent,
u are doing a good job by also mentioning the problem difficulty level.
Pls continue to do so that we can all benefit by it.


thanks
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by jnellaz » Wed Dec 17, 2008 11:24 am
Could someone re-post the question? Unfotunately, I am unable to see it in its current state. Best to all!
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by Brent@GMATPrepNow » Wed Dec 17, 2008 3:38 pm
The question involves roots, so it's not easy to write out, but here goes:

If (6th root of x) = 6, then root(x^6) = ?
A) 6
B) 6 root6
C) 6^6
D) 6^18
E) 6^36

Answer: D
Brent Hanneson - Creator of GMATPrepNow.com
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