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# GmatPrep #2 - exponents

Author Message
Manager
Joined: 19 Aug 2006
Posts: 239

Kudos [?]: 13 [0], given: 0

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23 Mar 2009, 11:52
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

An interesting problem.
I'll post the OA later.
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Kudos [?]: 13 [0], given: 0

CEO
Joined: 17 Nov 2007
Posts: 3584

Kudos [?]: 4590 [0], given: 360

Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
Re: GmatPrep #2 - exponents [#permalink]

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23 Mar 2009, 15:50
$$2+2+2^2+2^3+2^4+2^5+2^6+2^7+2^8$$ =

$$2^2+2^2+2^3+2^4+2^5+2^6+2^7+2^8$$ =

$$2^3+2^3+2^4+2^5+2^6+2^7+2^8$$ =

Do you see what the end is? $$2^8+2^8=2^9$$

Or just for fun:
in binary system: 11111111 + 00000001 = 100000000 (equivalent of 2^9)
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Kudos [?]: 4590 [0], given: 360

Manager
Joined: 05 Jan 2009
Posts: 80

Kudos [?]: 160 [0], given: 2

Re: GmatPrep #2 - exponents [#permalink]

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24 Mar 2009, 15:02
aLT: It's a GP series. 2 + 2(2^8-1)/(2-1)=2+2^9-2=2^9.

Kudos [?]: 160 [0], given: 2

Re: GmatPrep #2 - exponents   [#permalink] 24 Mar 2009, 15:02
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