GMAT Prep Math Practice Test Question

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GMAT Prep Math Practice Test Question

by damrkstr » Sun Nov 02, 2008 4:16 pm
Hi. I am going through my wrong answers from the 1st practice test on the GMAT Prep CD, and was hoping someone could help me out with some since there are no explanations on there.

1. Which of the following is equal to the value of 2^5 +2^5 + 3^5 + 3^5 + 3^5? and the answer was [spoiler]2^6 + 3^6[/spoiler]
I know that this is correct but are there any quick rules/techniques that can help get you to this answer faster? I know all of the multiplication exponent rules but they don't apply here.

Thanks. I am sure I'll be asking more questions on here.

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by dmateer25 » Sun Nov 02, 2008 4:43 pm
The rule for this is:

a^x + a^x = 2(a^x)
a^x + a^x + a^x = 3(a^x)


2^5 +2^5 + 3^5 + 3^5 + 3^5?

2(2^5) + 3(3^5)

2^6 + 3^6

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Re: GMAT Prep Math Practice Test Question

by logitech » Sun Nov 02, 2008 5:42 pm
damrkstr wrote:Hi. I am going through my wrong answers from the 1st practice test on the GMAT Prep CD, and was hoping someone could help me out with some since there are no explanations on there.

1. Which of the following is equal to the value of 2^5 +2^5 + 3^5 + 3^5 + 3^5? and the answer was [spoiler]2^6 + 3^6[/spoiler]
I know that this is correct but are there any quick rules/techniques that can help get you to this answer faster? I know all of the multiplication exponent rules but they don't apply here.

Thanks. I am sure I'll be asking more questions on here.
Guys make sure that you know the FUNDAMENTALS of basic math like inside of your palm.

Manhattan GMAT books will help you.
LGTCH
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by vishubn » Tue Nov 04, 2008 5:23 am
My Key to this kinda problem is to always find the common factor ! and reduce the given as much as possible !

believe me it works .. u do few problems on the same lane u will know wat exactly i mean :)

Infact u start liking it !! always look for the similar powers to take coomon factor out or to cancel out or bring similar powers on the same equation

Vishu

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by GMAT dreamer » Tue Nov 18, 2008 12:53 pm
The rule is x² + x² = 2x². Like terms.