Adding Exponents

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Adding Exponents

by Rudy414 » Mon May 20, 2013 1:51 pm
2^5 + 2^5 + 3^5 + 3^5 + 3^5 is equal to:

5^6
13^5
2^6 + 3^6
2^7 + 3^8
4^5 + 9^5

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by Brent@GMATPrepNow » Mon May 20, 2013 1:59 pm
Rudy414 wrote:2^5 + 2^5 + 3^5 + 3^5 + 3^5 is equal to:

A) 5^6
B) 13^5
C) 2^6 + 3^6
D) 2^7 + 3^8
E) 4^5 + 9^5
What we really have here is an algebra question involving the combining of like terms.

First, notice that K + K = 2K
Using the same logic, 2^5 + 2^5 = 2(2^5) = (2^1)(2^5) = 2^6

Similarly, notice that M + M + M = 3M
Using the same logic, 3^5 + 3^5 + 3^5 = 3(3^5) = (3^1)(3^5) = 3^6

So, 2^5 + 2^5 + 3^5 + 3^5 + 3^5 = 2^6 + 3^6

Answer: C

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Brent
Brent Hanneson - Creator of GMATPrepNow.com
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