November 14, 2018 November 14, 2018 07:00 PM PST 08:00 PM PST Join the webinar and learn timemanagement tactics that will guarantee you answer all questions, in all sections, on time. Save your spot today! Nov. 14th at 7 PM PST November 15, 2018 November 15, 2018 10:00 PM MST 11:00 PM MST EMPOWERgmat is giving away the complete Official GMAT Exam Pack collection worth $100 with the 3 Month Pack ($299)
Author 
Message 
TAGS:

Hide Tags

Manager
Joined: 16 May 2011
Posts: 189
Concentration: Finance, Real Estate
GMAT Date: 12272011
WE: Law (Law)

A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
[#permalink]
Show Tags
06 Jul 2011, 11:57
Question Stats:
66% (01:54) correct 34% (01:47) wrong based on 149 sessions
HideShow timer Statistics
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
Official Answer and Stats are available only to registered users. Register/ Login.



Retired Moderator
Joined: 20 Dec 2010
Posts: 1829

Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
[#permalink]
Show Tags
06 Jul 2011, 12:08
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"
_________________
~fluke
GMAT Club Premium Membership  big benefits and savings



Director
Joined: 01 Feb 2011
Posts: 664

Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
[#permalink]
Show Tags
07 Jul 2011, 15:45
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.



Current Student
Joined: 08 Jan 2009
Posts: 304

Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
[#permalink]
Show Tags
07 Jul 2011, 15:57
\(2^{10} = 1024\)
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.



Manager
Status: ==GMAT Ninja==
Joined: 08 Jan 2011
Posts: 198
Schools: ISB, IIMA ,SP Jain , XLRI
WE 1: Aditya Birla Group (sales)
WE 2: Saint Gobain Group (sales)

Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
[#permalink]
Show Tags
08 Jul 2011, 12:01
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
_________________
WarLocK _____________________________________________________________________________ The War is oNNNNNNNNNNNNN for 720+ see my Test exp here http://gmatclub.com/forum/mytestexperience111610.html do not hesitate me giving kudos if you like my post.



Manager
Joined: 17 May 2010
Posts: 247

Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
[#permalink]
Show Tags
08 Jul 2011, 17:58
10th term is 1024. So the reciprocal is between .001 and .0001. Hence C.
_________________
If you like my post, consider giving me KUDOS!



VP
Status: It's near  I can see.
Joined: 13 Apr 2013
Posts: 1282
Location: India
Concentration: International Business, Operations
GPA: 3.01
WE: Engineering (Consulting)

Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the
[#permalink]
Show Tags
01 Mar 2018, 01:56
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)
_________________
"Do not watch clock; Do what it does. KEEP GOING."




Re: A sequence of 10 integers is as follows: 2, 4, 8, 16, 32 ... If the &nbs
[#permalink]
01 Mar 2018, 01:56






