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A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
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06 Jul 2011, 12:57
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A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the reciprocal of the 10th term is x, then x should be in which of the following ranges? (A) 0.000001 < x < 0.00001 (B) 0.00001 < x < 0.0001 (C) 0.0001 < x < 0.001 (D) 0.001 < x < 0.01 (E) 0.01 < x < 0.1
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Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
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06 Jul 2011, 13:08
dimri10 wrote: A sequence of 10 integers is as follows: 2,4,8,16,32.... If the reciprocal of the 10th term is x, then x should be in which of the following ranges? (A) 0.000001< x <0.00001 (B) 0.00001< x <0.0001 (C) 0.0001< x <0.001 (D) 0.001< x <0.01 (E) 0.01< x <0.1 that's only my OA 10th term= 2^(10) Reciprocal = x= 1/2^(10)= 1/1024 x=1/1024 < 1/1000=0.001 x=1/1024 > 1/10000=0.0001 OR 0.0001<x 0.0001<x<0.001 Ans: "C"
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Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
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07 Jul 2011, 16:45
this series in G.P
so 10th term = ar^(n1)
a=2 r=2 ,n=10
=>10th term = 2^10
reciprocal of 10th term = 1/(2^10) = 1/1024
we know that 1/1000 > 1/1024 > 1/10000
ie 1/1000 > x > 1/10000
0.0001 <x<0.001
Answer is C.



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Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
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07 Jul 2011, 16:57
\(2^{10} = 1024\)
I think remembering powers of 2 is useful, although it's not hard to quickly calculate this from the pattern.
\(\frac{1}{1024}\), will be a little bit smaller than \(\frac{1}{1000}\) or .001, say .0009
C.



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Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
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08 Jul 2011, 13:01
dimri10 wrote: A sequence of 10 integers is as follows: 2,4,8,16,32.... If the reciprocal of the 10th term is x, then x should be in which of the following ranges? (A) 0.000001< x <0.00001 (B) 0.00001< x <0.0001 (C) 0.0001< x <0.001 (D) 0.001< x <0.01 (E) 0.01< x <0.1 that's only my OA reciprocal of 10th term is 1/5th term *1/5th term =1/32*1/32 = .03*.03 =.0009xxx so itsbigger than .0001 but lesser than .001 hope its simple
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Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
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08 Jul 2011, 18:58
10th term is 1024. So the reciprocal is between .001 and .0001. Hence C.
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Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
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01 Mar 2018, 02:56
dimri10 wrote: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the reciprocal of the 10th term is x, then x should be in which of the following ranges?
(A) 0.000001 < x < 0.00001 (B) 0.00001 < x < 0.0001 (C) 0.0001 < x < 0.001 (D) 0.001 < x < 0.01 (E) 0.01 < x < 0.1 x = 2^10 = 1024 (Better to remember powers of some numbers) We know, 1000 < 1024 < 10000 or 1/1000 > 1/1024 > 1/10000 or 0.0001 < x < 0.001 (C)
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