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Problem Solving — algebra and arithmetic (GMAT Focus Edition)
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by Brent@GMATPrepNow » Sat Feb 04, 2012 5:59 am
klaud wrote:3^5 + 3^5 + 3^5 = ?
This is a common question type on the GMAT, and it can take many forms.

This important thing to note here is that this question is really an Algebra question. The problem is that many students don't recognize it as so because there are no variables.

This question tests your ability to combine "like terms."
We know that y + y + y = 3y
And we know that x^2 + x^2 + x^2 = 3x^2
And we know that a^2b^5 + a^2b^5 + a^2b^5 = 3a^2b^5

So . . . 3^5 + 3^5 + 3^5 = (3)3^5
= (3^1)(3^5)
= 3^6

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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