What is the difference between the sum of the numbers from 1 : Quant Question Archive [LOCKED]
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 23 Jan 2017, 02:33

### 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 difference between the sum of the numbers from 1

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
Manager
Joined: 08 Jul 2006
Posts: 89
Followers: 1

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

What is the difference between the sum of the numbers from 1 [#permalink]

### Show Tags

12 Oct 2006, 12:36
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

What is the difference between the sum of the numbers from 1 to 600 and the sum of the even numbers from 460 to 600, inclusive?

a) 180300
b) 142670
c) 371000
d) 124760
e) 359540
Manager
Joined: 08 Jul 2006
Posts: 89
Followers: 1

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

### Show Tags

12 Oct 2006, 13:20
Cicerone, can you show how you derive your answers, please?
Senior Manager
Joined: 28 Aug 2006
Posts: 306
Followers: 13

Kudos [?]: 150 [0], given: 0

### Show Tags

12 Oct 2006, 13:30
Sum of the first n natural numbers is n(n+1)/2.

So sum of the first 600 numbers is 600x601/2 = 300x601=180300

Next even numbers from 460 to 600

i.e. 460,462,464,...........................596.598,600

Totally there will be 141 numbers from 460 to 600
Out of these 141 numbers, 71 will even and 70 will be odd.

I mean to say that from 460 to 600 there will be 71 even numbers.

So the sum of the above series (which is in ARITHMETIC PROGRESSION) will be N/2(FIRST TERM + LAST TERM), where N = number of terms in the series.

So 71/2(460+600) = 71x530 = 37630.

Hence the answer will be 180300-37630=142,670
_________________
Director
Joined: 23 Jun 2005
Posts: 847
GMAT 1: 740 Q48 V42
Followers: 5

Kudos [?]: 70 [0], given: 1

### Show Tags

12 Oct 2006, 18:19
B

Sum of all numbers from 1-600 = 600/2(1+600) = 180300

Number of all even numbers from 460 - 600 = 600-460/2 = 70.5 = 71 (Since starting and ending numbers are even, there will be one more even number than odd numbers).

Sum of all even numbers from 460-600 = 71/2(460+600) = 37630

Difference = 142670
Senior Manager
Joined: 30 Aug 2006
Posts: 374
Followers: 3

Kudos [?]: 65 [0], given: 0

### Show Tags

13 Oct 2006, 12:41
B

sum of 1-600 = 601/2 * 600 = 180300

sum of evens = 1060/2 * 71 = 530 * 71 = 37630

= 142760
13 Oct 2006, 12:41
Display posts from previous: Sort by

# What is the difference between the sum of the numbers from 1

 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®.