Find all School-related info fast with the new School-Specific MBA Forum

It is currently 15 Apr 2014, 20:29

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

What is the value of 1*1! + 2*2! + 3!*3! + ............

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Current Student
User avatar
Joined: 29 Jan 2005
Posts: 5253
Followers: 21

Kudos [?]: 110 [0], given: 0

GMAT Tests User Reviews Badge
What is the value of 1*1! + 2*2! + 3!*3! + ............ [#permalink] New post 29 Oct 2005, 09:09
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
What is the value of 1*1! + 2*2! + 3!*3! + ............ n*n!,
where n! means n factorial or n(n-1)(n-2)...1

(1) n(n-1)(n-1)!
(2) (n+1)!/(n(n-1))
(3) (n+1)! - n!
(4) (n + 1)! - 1!
(5) n!(n-1)
Current Student
User avatar
Joined: 23 Oct 2005
Posts: 244
Schools: Cranfield SOM
Followers: 2

Kudos [?]: 13 [0], given: 2

GMAT Tests User
 [#permalink] New post 29 Oct 2005, 12:39
Substituting 3 for n we get the option D as the correct answer.
SVP
SVP
User avatar
Joined: 24 Sep 2005
Posts: 1902
Followers: 9

Kudos [?]: 75 [0], given: 0

GMAT Tests User
Re: PS: P/C Ascent 5/02 [#permalink] New post 29 Oct 2005, 18:48
GMATT73 wrote:
What is the value of 1*1! + 2*2! + 3!*3! + ............ n*n!,
where n! means n factorial or n(n-1)(n-2)...1

(1) n(n-1)(n-1)!
(2) (n+1)!/(n(n-1))
(3) (n+1)! - n!
(4) (n + 1)! - 1!
(5) n!(n-1)


1*1!+2*2!+3*3!+......+n*n!
= (2-1)*1! + (3-1)*2! + (4-1)*3! + ...+ [(n+1)-1]*n!
=(2*1! - 1!) + (3*2! - 2!) + ( 4*3! - 3!)+ ......+ [(n+1)*n! - n!]
= 2! - 1! + 3! - 2! + 4!- 3! + ......+ (n+1)! - n!
= -(1!) + (2!- 2!) + (3!-3!) + ( 4!-4!) + .....+ (n!-n!) + (n+1)!
= -(1!) + 0 + 0 + 0 + + 0 + (n+1)!
= (n+1)! - 1!
D it is!
Re: PS: P/C Ascent 5/02   [#permalink] 29 Oct 2005, 18:48
    Similar topics Author Replies Last post
Similar
Topics:
New posts Find the value of 1*1! + 2*2! + 3*3! + ......+n*n! (1) christoph 2 07 May 2005, 06:35
New posts What is the value of 1*1! + 2*2! + 3*3! + ............ n*n!, cool_jonny009 4 08 Nov 2005, 09:12
New posts What is the highest power of 2 dividing 1^1 * 2^2 * 3^3 * sm176811 1 14 Apr 2006, 16:09
New posts 5^11 x 4^11= 2 x 10^n, what is the value of n? 11 21 22 lan583 7 25 Aug 2006, 05:07
New posts If 5^21 * 4^11 = 2*10^n, what is the value of n? 11 21 22 23 uphillclimb 7 21 Oct 2006, 09:56
Display posts from previous: Sort by

What is the value of 1*1! + 2*2! + 3!*3! + ............

  Question banks Downloads My Bookmarks Reviews Important topics  


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®.