Find all School-related info fast with the new School-Specific MBA Forum
Learn more about the recent changes... close

It is currently 22 May 2013, 03:44
Customize  |  Hide

Search
Register
New posts
Unanswered

If D is the sum of the reciprocals of the consecutive

  Question banks Downloads My Bookmarks Reviews  
  Oldest Best Reply
Search for:
 
Print view
First unread post
Author Message
TAGS:
Manager
Manager
Joined: 11 Jan 2007
Posts: 206
Location: Bangkok
Followers: 1

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

GMAT Tests User
If D is the sum of the reciprocals of the consecutive [#permalink] New post 28 Jul 2007, 09:45
17. If D is the sum of the reciprocals of the consecutive integers from 91 to 100, inclusive, which of the following is less than D?
I. 1/8
II. 1/9
III. 1/10
A. None
B. I only
C. III only
D. II and III only
E. I, II, and III
_________________

cool

Manager
Manager
Joined: 08 Jul 2007
Posts: 175
Followers: 1

Kudos [?]: 1 [0], given: 0

GMAT Tests User
 [#permalink] New post 28 Jul 2007, 10:23
C.

The average of those recipricals is ((1/91)+(1/100))/2=(1/95.5). There are 10 integers between 1/91 and 1/100 inclusive. So the sum of the integers is 10/95.5 or 100/955>100/1000=1/10. So III is less than D.

For II, 1/9=100/900>100/955. This means that I and II are greater than D.
Senior Manager
Senior Manager
Joined: 04 Jun 2007
Posts: 357
Followers: 1

Kudos [?]: 9 [0], given: 0

GMAT Tests User
Re: Integers [#permalink] New post 28 Jul 2007, 11:56
jet1445 wrote:
17. If D is the sum of the reciprocals of the consecutive integers from 91 to 100, inclusive, which of the following is less than D?
I. 1/8
II. 1/9
III. 1/10
A. None
B. I only
C. III only
D. II and III only
E. I, II, and III


D = 1/91 + 1/92 + ... + 1/100

hence, 10/91 > D > 10/100
or, 10/91 > D > 1/10

Since 1/9 (or 10/90) > 10/91, so D is less than both 1/9 and 1/8.

So, only 1/10 is less than D.

Answer is C.
Re: Integers   [#permalink] 28 Jul 2007, 11:56
    Similar topics Author Replies Last post
Similar
Topics:
 New posts If S is the sum of the reciprocals of the consecutive JAI HIND 7 23 Dec 2005, 02:19
New posts S is the sum of the reciprocal of a list of consecutive laxieqv 5 09 Jun 2006, 10:42
New posts 3 EXPERTS_POSTS_IN_THIS_TOPIC If S is the sum of reciprocals of a list of consecutive gmihir 6 16 May 2012, 09:35
New posts 4 M is the sum of the reciprocals of the consecutive integers sarb 2 07 Jun 2012, 01:14
New posts 12 EXPERTS_POSTS_IN_THIS_TOPIC M is the sum of the reciprocals of the consecutive integers Walkabout 5 06 Dec 2012, 09:42
Display posts from previous: Sort by

If D is the sum of the reciprocals of the consecutive

  Question banks Downloads My Bookmarks Reviews  
Print view
First unread post

Moderators: Bunuel, VeritasPrepKarishma

Search for:


GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.

Main navigation

GMAT Resources

Partners

MBA Resources

www.gmac.com|www.mba.com