It is currently 22 Jun 2017, 17:12

### 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

# The sum of all the integers k such that –26 < k < 24 is

Author Message
TAGS:

### Hide Tags

Manager
Joined: 06 Apr 2010
Posts: 146
The sum of all the integers k such that –26 < k < 24 is [#permalink]

### Show Tags

27 Aug 2010, 23:09
00:00

Difficulty:

(N/A)

Question Stats:

75% (01:15) correct 25% (00:00) wrong based on 4 sessions

### HideShow timer Statistics

The sum of all the integers k such that –26 < k < 24 is

A. 0
B. -2
C. -25
D. -49
E. -51

What is the trap here...I am getting answer as -51 where as OA is diff.
[Reveal] Spoiler: OA
Manager
Joined: 09 Jun 2010
Posts: 113
Re: The sum of all the integers k such that –26 < k < 24 is [#permalink]

### Show Tags

28 Aug 2010, 07:11
-25------------------0-----------------23

values upto + 23 cancels out & we are left with only -25 & -24 sum of which is - 49. hence option D.

Since this is in equality we dont consider -26 and 24 as values of K. K is greater than -26 & less than +24 therefore range of K is -25 to 23. You might be considering -26 & 24, in that case the range becomes -26 to +24 and the answer will be 51 which is wrong.
Math Expert
Joined: 02 Sep 2009
Posts: 39589
The sum of all the integers k such that –26 < k < 24 is [#permalink]

### Show Tags

28 Aug 2010, 07:21
udaymathapati wrote:
The sum of all the integers k such that –26 < k < 24 is
A. 0
B. -2
C. -25
D. -49
E. -51

What is the trap here...I am getting answer as -51 where as OA is diff.

Notice that the range is not inclusive: k can not be -26 or 24! That's why you are getting -51.

The sum will be: (-25)+(-24)+(-23)+...+(-1)+0+1+..+23 --> the sum of pairs -23 and 23, -22 and 22 and so on is 0 and we are left only with -25+(-24)=-49.

Or: as we have evenly spaced set: the sum will be average of the first and the last terms multiplied be the # of terms: $$\frac{-25+23}{2}*49=-49$$.

Hope it's clear.
_________________
Director
Status: No dream is too large, no dreamer is too small
Joined: 14 Jul 2010
Posts: 633
The sum of all the integers k such that -26 < k < 24 is [#permalink]

### Show Tags

03 Jan 2012, 09:16
1
KUDOS
2
This post was
BOOKMARKED
The sum of all the integers k such that -26 < k < 24 is

A. 0
B. -2
C. -25
D. -49
E. -51

[Reveal] Spoiler:
Whether the following approach correct?
K takes value form -25 to 23
Thus number of values (n) 23+25+1 = 49
Now, n(a1+an)/2
49(-25+23)/2 = -49

_________________

Collections:-
PSof OG solved by GC members: http://gmatclub.com/forum/collection-ps-with-solution-from-gmatclub-110005.html
DS of OG solved by GC members: http://gmatclub.com/forum/collection-ds-with-solution-from-gmatclub-110004.html
100 GMAT PREP Quantitative collection http://gmatclub.com/forum/gmat-prep-problem-collections-114358.html
Collections of work/rate problems with solutions http://gmatclub.com/forum/collections-of-work-rate-problem-with-solutions-118919.html
Mixture problems in a file with best solutions: http://gmatclub.com/forum/mixture-problems-with-best-and-easy-solutions-all-together-124644.html

Last edited by Bunuel on 04 Sep 2015, 05:33, edited 2 times in total.
Renamed the topic and edited the question.
Senior Manager
Joined: 11 May 2011
Posts: 361
Location: US
Re: The sum of all the integers k such that -26 < k < 24 is [#permalink]

### Show Tags

03 Jan 2012, 09:58
2
KUDOS
Baten80 wrote:
The sum of all the integers k such that -26<k<24 is
A. 0
B. -2
C. -25
D. -49
E. -51

Easy one -
-25, -24, -23,-22,...... -1,0, 1, 2...., 22, 23
Cancel everyhitng and we're left with - -25 and -24 = -49.

Cheers!
_________________

-----------------------------------------------------------------------------------------
What you do TODAY is important because you're exchanging a day of your life for it!
-----------------------------------------------------------------------------------------

Senior Manager
Joined: 13 May 2011
Posts: 307
WE 1: IT 1 Yr
WE 2: Supply Chain 5 Yrs
Re: The sum of all the integers k such that -26 < k < 24 is [#permalink]

### Show Tags

03 Jan 2012, 11:10
1
KUDOS
or: if we have enough time, we can use the following formula, since its an AP:
sum=n/2*{2a+(n-1)*d}
a= -25, d=1, n=49 (including 0)
therefore, sum= 49/2(-50+48)
=-49
Manager
Joined: 29 Jul 2011
Posts: 107
Location: United States
Re: The sum of all the integers k such that -26 < k < 24 is [#permalink]

### Show Tags

04 Jan 2012, 13:05
1
KUDOS
Sum = mean X number of elements
mean = [23 + (-24)]/2 = -1
number = [23 - (-24)]/1 + 1 = 49
Sum = -1 x 49 = -49
_________________

I am the master of my fate. I am the captain of my soul.
Please consider giving +1 Kudos if deserved!

DS - If negative answer only, still sufficient. No need to find exact solution.
PS - Always look at the answers first
CR - Read the question stem first, hunt for conclusion
SC - Meaning first, Grammar second
RC - Mentally connect paragraphs as you proceed. Short = 2min, Long = 3-4 min

Intern
Joined: 17 Oct 2011
Posts: 11
Re: The sum of all the integers k such that -26 < k < 24 is [#permalink]

### Show Tags

04 Jan 2012, 22:18
C

Mean = (-25 + 23)/2 = -1
Number count = 25 + 23 + 1 = 49
Sum = Mean * Count = -49
_________________

We will either find a way, or make one.

Please consider giving kudos if you find my post hepful

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 15916
Re: The sum of all the integers k such that -26 < k < 24 is [#permalink]

### Show Tags

04 Sep 2015, 02:09
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: The sum of all the integers k such that -26 < k < 24 is   [#permalink] 04 Sep 2015, 02:09
Similar topics Replies Last post
Similar
Topics:
What is the largest integer k for which 81^k < 3^27 ? 4 15 Jun 2017, 16:32
1 How many possible positive integer values are there for k if -24 < 9k 2 14 Nov 2016, 00:01
18 The sum of all the integers k such that −26 < k < 24 is 12 14 Jun 2017, 07:30
8 If k is an integer and 121 < k^2 < 225, then k can have at most how 12 15 Jan 2017, 07:20
33 If k is an integer and 2 < k < 7, for how many different 15 19 Jun 2017, 11:12
Display posts from previous: Sort by