Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

 It is currently 24 May 2017, 09:15

# Live Now:

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# What is the range ans sum of of Sn Sn=

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
SVP
Joined: 05 Jul 2006
Posts: 1747
Followers: 6

Kudos [?]: 358 [0], given: 49

What is the range ans sum of of Sn Sn= [#permalink]

### Show Tags

13 Oct 2006, 13:58
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

What is the range ans sum of of Sn
Sn= 1/34+1/35+1/36+1/37......+1/66
Director
Joined: 23 Jun 2005
Posts: 841
GMAT 1: 740 Q48 V42
Followers: 6

Kudos [?]: 76 [0], given: 1

### Show Tags

13 Oct 2006, 19:28
Range: 1/34 - 1/66 = 8/187

Sum: 33/2(1/33 + 1/66) = 25/34

The highlighted part should be 34. Explanation two posts below.

(edited to correct typo)

Last edited by anandsebastin on 13 Oct 2006, 20:43, edited 1 time in total.
Manager
Joined: 07 Jun 2006
Posts: 110
Followers: 2

Kudos [?]: 29 [0], given: 0

### Show Tags

13 Oct 2006, 20:31
Code:
Sum: 33/2(1/33 + 1/66) = 25/34

Anand, pls explain.
Director
Joined: 23 Jun 2005
Posts: 841
GMAT 1: 740 Q48 V42
Followers: 6

Kudos [?]: 76 [0], given: 1

### Show Tags

13 Oct 2006, 20:40
girikorat wrote:
Sum: 33/2(1/33 + 1/66) = 25/34

Anand, pls explain.

Sorry Giri!

Sum of a series = n/2(a+l)
where, n = number of terms
a = first term
l = last term

Here, 1/33 to 1/66. So n=66-34 +1 (since 34 is also included)

I made a typo (highlighted) in the original post. It should be

33/2(1/34+1/66)

Hope that is right and is of help!
Senior Manager
Joined: 28 Aug 2006
Posts: 304
Followers: 13

Kudos [?]: 153 [0], given: 0

### Show Tags

13 Oct 2006, 22:22
Folks, u r doing a mistake here.

Sum of the series will be n/2 (a+l) provided the given series is in Arithmetic Series.

But in the above question , the series is in Harmonic Series.......

So u can't apply this formula to calculate the sum
_________________
Director
Joined: 23 Jun 2005
Posts: 841
GMAT 1: 740 Q48 V42
Followers: 6

Kudos [?]: 76 [0], given: 1

### Show Tags

14 Oct 2006, 09:21
cicerone wrote:
Folks, u r doing a mistake here.

Sum of the series will be n/2 (a+l) provided the given series is in Arithmetic Series.

But in the above question , the series is in Harmonic Series.......

So u can't apply this formula to calculate the sum

Cicerone,
Is the formula to find out the sum of n terms of a harmonic series ln(n+1), where
l = last term
n =number of terms.

If so, answer would be
(1/66)*33*34 = 17
14 Oct 2006, 09:21
Display posts from previous: Sort by

# What is the range ans sum of of Sn Sn=

 post reply Question banks Downloads My Bookmarks Reviews Important topics

 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®.