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# 20^5*5^10*8^2/10^5

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Intern
Joined: 26 Apr 2018
Posts: 39

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Updated on: 11 Jan 2019, 10:10
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Difficulty:

15% (low)

Question Stats:

81% (01:35) correct 19% (01:58) wrong based on 87 sessions

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$$\frac{20^{5}*5^{10}*8^{2}}{10^{5}}$$

A. $$2^{11}$$$$5^{10}$$

B. $$2^{60}5^{50}$$

C. $$2^{16}5^{15}$$

D. $$2^{16}3^{10}10^{8}$$

E. $$2^{8}5^{20}10^{5}$$

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Originally posted by bettatantalo on 20 Sep 2018, 07:14.
Last edited by Bunuel on 11 Jan 2019, 10:10, edited 2 times in total.
Intern
Joined: 30 Mar 2017
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Location: United States (FL)

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20 Sep 2018, 07:30
This is wrong. The answer should be :
2^11 * 5 ^ 10

Love how the first question I tried after deciding to try again for an MBA has an error in it...
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20 Sep 2018, 07:37
bettatantalo wrote:
$$20^{5}*5^{10}*8^{2}/10^{5}$$

a) $$2^{11}$$
b) $$2^{60}5^{50}$$
c) $$2^{16}5^{15}$$
d) $$2^{16}3^{10}10^{8}$$
e) $$2^{8}5^{20}10^{5}$$

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$$\frac{20^{5}*5^{10}*8^{2}}{10^{5}}$$

= $$\frac{2^{16}*5^{15}}{2^{5}*5^5}$$

= $$2^{11}*5^{10}$$

None of the Answer matches, please check the OA and options, IMHO U missed $$5^{10}$$ in option (A)
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Abhishek....

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Intern
Joined: 26 Apr 2018
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20 Sep 2018, 07:51
laxpro2001 wrote:
This is wrong. The answer should be :
2^11 * 5 ^ 10

Love how the first question I tried after deciding to try again for an MBA has an error in it...

So sorry my bad, all those symbols when writing the question confused me
Intern
Joined: 26 Apr 2018
Posts: 39

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20 Sep 2018, 07:54
Abhishek009 wrote:
bettatantalo wrote:
$$20^{5}*5^{10}*8^{2}/10^{5}$$

a) $$2^{11}$$
b) $$2^{60}5^{50}$$
c) $$2^{16}5^{15}$$
d) $$2^{16}3^{10}10^{8}$$
e) $$2^{8}5^{20}10^{5}$$

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$$\frac{20^{5}*5^{10}*8^{2}}{10^{5}}$$

= $$\frac{2^{16}*5^{15}}{2^{5}*5^5}$$

= $$2^{11}*5^{10}$$

None of the Answer matches, please check the OA and options, IMHO U missed $$5^{10}$$ in option (A)

Hi! I don't quite get what you did to get to this $$\frac{2^{16}*5^{15}}{2^{5}*5^5}$$

Thank you
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20 Sep 2018, 08:00
1
bettatantalo wrote:
Hi! I don't quite get what you did to get to this $$\frac{2^{16}*5^{15}}{2^{5}*5^5}$$

Thank you

$$20^5 = (2^2*5)^5 = 2^{10}*5^5$$

$$8^2 = (2^3)^2 = 2^6$$

Now, add the top row -

$$20^5*5^{10}*8^2 = 2^{10}*5^5*5^{10}*2^6 = 2^{16}*5^{15}$$

bettatantalo wrote:
So sorry my bad, all those symbols when writing the question confused me

No issues, dude we do understand that !!! Keep poring in ...
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Thanks and Regards

Abhishek....

PLEASE FOLLOW THE RULES FOR POSTING IN QA AND VA FORUM AND USE SEARCH FUNCTION BEFORE POSTING NEW QUESTIONS

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20 Sep 2018, 22:25
20^5 x 5^10 x 8^2/10^5

=>2^5 x 5^10 x 8^2
(((8^2 = 2^3x2=2^6)))

=>2^5 x 2^6 x 5^10
(((Apply the property x^m.x^n = x^m+n)))

=>2^11 x 5^10

Thank you
Arjun
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11 Jan 2019, 10:05
bettatantalo wrote:
$$20^{5}*5^{10}*8^{2}/10^{5}$$

a) $$2^{11}$$$$5^{10}$$
b) $$2^{60}5^{50}$$
c) $$2^{16}5^{15}$$
d) $$2^{16}3^{10}10^{8}$$
e) $$2^{8}5^{20}10^{5}$$

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Dear Moderator,
Can we format this question properly, initially was confused if the question was :
$$20^{5}*5^{10}* \frac{8^{2}}{10^{5}}$$ or $$\frac{ 20^{5}*5^{10}*8^{2}}{10^{5}}$$
Thank you.
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- Stne
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Joined: 02 Sep 2009
Posts: 55803

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11 Jan 2019, 10:09
1
stne wrote:
bettatantalo wrote:
$$20^{5}*5^{10}*8^{2}/10^{5}$$

a) $$2^{11}$$$$5^{10}$$
b) $$2^{60}5^{50}$$
c) $$2^{16}5^{15}$$
d) $$2^{16}3^{10}10^{8}$$
e) $$2^{8}5^{20}10^{5}$$

Source gmat tutor

Dear Moderator,
Can we format this question properly, initially was confused if the question was :
$$20^{5}*5^{10}* \frac{8^{2}}{10^{5}}$$ or $$\frac{ 20^{5}*5^{10}*8^{2}}{10^{5}}$$
Thank you.

Those two expression are mathematically identical. Still edited.
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Joined: 09 Mar 2018
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11 Jan 2019, 10:21
bettatantalo wrote:
$$\frac{20^{5}*5^{10}*8^{2}}{10^{5}}$$
A. $$2^{11}$$$$5^{10}$$

B. $$2^{60}5^{50}$$

C. $$2^{16}5^{15}$$

D. $$2^{16}3^{10}10^{8}$$

E. $$2^{8}5^{20}10^{5}$$

$$\frac{(2*2*5)^{5}*5^{10}*(2*2*2)^{2}}{(2*5)^{5}}$$

$$\frac{2^{10}* 5^{15}* 2^{6}}{(2)^{5}* (5)^{5}}$$

$$2^{11}$$$$5^{10}$$

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11 Jan 2019, 11:32
Bunuel wrote:
stne wrote:
bettatantalo wrote:
$$20^{5}*5^{10}*8^{2}/10^{5}$$

a) $$2^{11}$$$$5^{10}$$
b) $$2^{60}5^{50}$$
c) $$2^{16}5^{15}$$
d) $$2^{16}3^{10}10^{8}$$
e) $$2^{8}5^{20}10^{5}$$

Source gmat tutor

Dear Moderator,
Can we format this question properly, initially was confused if the question was :
$$20^{5}*5^{10}* \frac{8^{2}}{10^{5}}$$ or $$\frac{ 20^{5}*5^{10}*8^{2}}{10^{5}}$$
Thank you.

Those two expression are mathematically identical. Still edited.

Thank you, in a hurry , did not realize that both the expressions would give same result.
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- Stne
Re: 20^5*5^10*8^2/10^5   [#permalink] 11 Jan 2019, 11:32
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