stumped on exponent problem

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stumped on exponent problem

by myfavoritething » Wed Oct 08, 2008 9:05 am
Hey y'all -

I'm going over missed answers from the MBA.com test prep download practice test and I'm stumped on one of the problem solving questions. Can anyone tell me how to figure out this answer?

Question:

If (1/5)^m(1/4)^18 = 1/2(10)^35 then m = ?

The "^" means exponent. 1/5 is being raised to the m power, 1/4 to the 18th power, which equals 1 over 2 times 10 to the 35th power.


I answered 17, which is incorrect. The correct answer is 35. Why?

I don't know how to combine different exponents..
Source: — Problem Solving |

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Re: stumped on exponent problem

by myfavoritething » Wed Oct 08, 2008 9:14 am
Nevermind! Found the answer on the forum. :)

[url]
https://www.beatthegmat.com/help-with-a- ... 19456.html[/url]

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by myfavoritething » Wed Oct 08, 2008 9:18 am
Nevermind. Found answer on the forum. :)

[url]https://www.beatthegmat.com/help-with-a- ... 19456.html[/url]

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by gupta.amit3 » Wed Oct 08, 2008 9:22 am
(1/5)^m(1/4)^18 = 1/2(10)^35 can be written as:

5^(-m)2^(-36) = 2^(-1)(2X5)^(-35) = 2^(-1-35)5^(-35)

Equating exponents on each side

-m=-35

Hence m=35 is ANS

Junior | Next Rank: 30 Posts
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by gupta.amit3 » Wed Oct 08, 2008 9:23 am
(1/5)^m(1/4)^18 = 1/2(10)^35 can be written as:

5^(-m)2^(-36) = 2^(-1)(2X5)^(-35) = 2^(-1-35)5^(-35)

Equating exponents on each side

-m=-35

Hence m=35 is ANS