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by yvonne12 » Wed Mar 07, 2007 3:26 pm
if n= 1/3 +1/3^2+1/3^3 then N is between

0 and 1/9
1/9 and 1/3
1/3 and 8/9
8/9 and 4/3
4/3 and 2

pls explain
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by ssiva » Wed Mar 07, 2007 4:08 pm
1/3 + (1/3)(1/3) + (1/3)(1/3)(1/3) = 0.333 + 0.333/3 + 0.3333/9
= 0.333 + 0.111 + 0.03 = 0.474

It is between 1/3 and 8/9
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by Jeff@TargetTestPrep » Sun Jun 17, 2018 7:10 pm
yvonne12 wrote:if n= 1/3 +1/3^2+1/3^3 then N is between

0 and 1/9
1/9 and 1/3
1/3 and 8/9
8/9 and 4/3
4/3 and 2
We can simplify and then add together the terms in the given equation:

n = 1/3 + 1/3^2 + 1/3^3

n = 1/3 + 1/9 + 1/27

n = 9/27 + 3/27 + 1/27 = 13/27

We see that 13/27 is slightly less than 1/2; thus, n is between 1/3 and 8/9.

Answer: C

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by Brent@GMATPrepNow » Mon Jun 18, 2018 5:51 am
yvonne12 wrote:if n= 1/3 +1/3^2+1/3^3 then N is between

0 and 1/9
1/9 and 1/3
1/3 and 8/9
8/9 and 4/3
4/3 and 2

pls explain
n= 1/3 + 1/3^2 + 1/3^3
= 1/3 + 1/9 + 1/27
= 9/27 + 3/27 + 1/27
= 13/27
≈ 1/2

Answer: C

Cheers,
Brent
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