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Let A=5^30, B=2^70, and C=3^40. Which of the following is true?
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Updated on: 10 Oct 2017, 07:39
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Let A=5^30, B=2^70, and C=3^40. Which of the following is true? A. A<B<C B. A<C<B C. B<A<C D. C<A<B E. C<B<A
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Originally posted by MathRevolution on 10 Oct 2017, 06:08.
Last edited by Bunuel on 10 Oct 2017, 07:39, edited 2 times in total.
Edited the question.



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Re: Let A=5^30, B=2^70, and C=3^40. Which of the following is true?
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10 Oct 2017, 06:33
Please correct the question. There’s a typo error Posted from my mobile device
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Re: Let A=5^30, B=2^70, and C=3^40. Which of the following is true?
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10 Oct 2017, 07:02



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Let A=5^30, B=2^70, and C=3^40. Which of the following is true?
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Updated on: 10 Oct 2017, 08:04
MathRevolution wrote: Let (CHANGED from what I originally quoted) A=5^30, B=2^70, and C=3^40.
Which of the following is true?
A. A<B<C B. A<C<B C. B<A<C D. C<A<B E. C<B<A Make all the exponents the same. They are all multiples of 10. \(a^{(nm)} = (a^{n})^{m}\) A = \(5^{30} = (5^3)^{10}\) B = \(2^{70}\) = \((2^7)^{10}\) C = \(3^{40}\) = \((3^4)^{10}\)  A= \((125)^{10}\) B = \((128)^{10}\) C = \((81)^{10}\) Now there are manageable bases all to the 10th power. Answer changed after question was edited C < A < B ANSWER D EDITED: my original answer changed after the question was edited. I also changed material in quotations to reflect Bunuel 's edit
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Originally posted by generis on 10 Oct 2017, 07:34.
Last edited by generis on 10 Oct 2017, 08:04, edited 3 times in total.



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Re: Let A=5^30, B=2^70, and C=3^40. Which of the following is true?
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10 Oct 2017, 07:40



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Let A=5^30, B=2^70, and C=3^40. Which of the following is true?
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Updated on: 10 Oct 2017, 07:51
Bunuel wrote: genxer123 wrote: MathRevolution wrote: Let A=5^30, C=2^70, and B=3^40. Which of the following is true?
A. A<B<C B. A<C<B C. B<A<C D. C<A<B E. C<B<A Hmm. I get Answer C Make all the exponents the same. They're multiples of 10. \(a^{(nm)} = (a^{n})^{m}\) A = \(5^{30} = (5^3)^{10}\) C = \(2^{70}\) = \((2^7)^{10}\) B = \(3^{40}\) = \((3^4)^{10}\)  A= \((125)^{10}\) C = \((128)^{10}\) B = \((81)^{10}\) Now there are manageable bases all to the 10th power. B < A < C Bunuel , is the OA correct? There was a typo. The correct ordering is 2^70 > 5^30 > 3^40. But the signs haven't been changed. They still say "<" Maybe I'm confused ( wouldn't be the first time) but I think the answer is C If 2(C) > 5(A) > 3 (B) then B < A < C That is ANSWER C... maybe I'm missing something.
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Originally posted by generis on 10 Oct 2017, 07:44.
Last edited by generis on 10 Oct 2017, 07:51, edited 1 time in total.



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Re: Let A=5^30, B=2^70, and C=3^40. Which of the following is true?
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10 Oct 2017, 07:49



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Let A=5^30, B=2^70, and C=3^40. Which of the following is true?
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10 Oct 2017, 07:52
Bunuel wrote: genxer123 wrote: But the signs haven't been changed. They still say "<" Correct answer: D. C<A<B (C=3^40) < (A=5^30) < (B=2^70) Brain fog  thanks. I kept looking at the prompt as I had quoted it in the original.
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Re: Let A=5^30, B=2^70, and C=3^40. Which of the following is true?
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12 Oct 2017, 01:46
A=5^30=(5^3)^10=125^10, B=2^70=(2^7)^10=128^10, and C=3^40=(3^4) ^10=81^10. Since their bases with the exponents 10 are 125, 128 and 81, C < A < B. Therefore, the answer is D.
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Re: Let A=5^30, B=2^70, and C=3^40. Which of the following is true? &nbs
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