NEW HERE? LEARN MORE
closeclose
Last visit was: 24 Apr 2024, 12:37 It is currently 24 Apr 2024, 12:37
Decision Tracker
My Rewards
New posts
New comers' posts

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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

S is the product of a list of consecutive integers from 1 to

User avatar
kook44
Manager
Manager
Joined: 23 Jan 2006
Posts: 91
Own Kudos [?]: 263 [0]
Given Kudos: 0
Send PM
S is the product of a list of consecutive integers from 1 to [#permalink] New post   31 May 2006, 06:40
S is the product of a list of consecutive integers from 1 to 24, and 10 k is a factor of S. What greatest value of k?
A: 1
B: 2
C: 3
D: 4
E: 5



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block below for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
User avatar
tapan22
Manager
Manager
Joined: 29 Sep 2005
Posts: 77
Own Kudos [?]: 2 [0]
Given Kudos: 0
Send PM
Re: S is the product of a list of consecutive integers from 1 to [#permalink] New post   31 May 2006, 06:55
S is the product of a list of consecutive integers from 1 to 24, and 10 k is a factor of S. What greatest value of k?
A: 1
B: 2
C: 3
D: 4
E: 5

**********************************************

Is it E)--5?

Since this is a product of consecutive integers and 10K is a factor of S so,

A: 10*1 is a factor
B: 10*2 is a factor
C: 10*3 is a factor
D: 10*4 is a factor
E: 10*5 is a factor -----> Greatest value of K is 5
User avatar
kook44
Manager
Manager
Joined: 23 Jan 2006
Posts: 91
Own Kudos [?]: 263 [0]
Given Kudos: 0
Send PM
Re: S is the product of a list of consecutive integers from 1 to [#permalink] New post   31 May 2006, 07:42
Argh.
I was originally puzzled by this question. It was written wrong. Should be:

S is the product of a list of consecutive integers from 1 to 24, and 10^k is a factor of S. What greatest value of k?
A: 1
B: 2
C: 3
D: 4
E: 5

got it now....
User avatar
tapan22
Manager
Manager
Joined: 29 Sep 2005
Posts: 77
Own Kudos [?]: 2 [0]
Given Kudos: 0
Send PM
Re: S is the product of a list of consecutive integers from 1 to [#permalink] New post   31 May 2006, 08:14
In that case is the answer 3?

I am not sure if this is the right approach though

I broke up each of the choices or powers of 10 into the primes:

10^1 = 5*2 --->divsible since both 2 and 5 are in the series
10^2 = 5*2*2--->divisible since both 4 and 4 are in the series
10^3 = (5*2)(5*2*2)*5 = 10*20*5-->divisible since all nos are in the series.
Fails for the rest of the choices
User avatar
tapan22
Manager
Manager
Joined: 29 Sep 2005
Posts: 77
Own Kudos [?]: 2 [0]
Given Kudos: 0
Send PM
Re: S is the product of a list of consecutive integers from 1 to [#permalink] New post   31 May 2006, 10:14
Professor what was the approach you took to arrive at 4? Can you pls explain?
User avatar
M8
Manager
Manager
Joined: 08 Jun 2004
Posts: 194
Own Kudos [?]: 215 [0]
Given Kudos: 0
Location: Europe
Send PM
Re: S is the product of a list of consecutive integers from 1 to [#permalink] New post   31 May 2006, 10:42
tapan22 wrote:
Professor what was the approach you took to arrive at 4? Can you pls explain?


D it is, 4.

There are just 4 10s.
2*5 = 10
10 by itself
4*15 =60 = 10*6
20 = 10 *2

No digits left that give us zero at the end.
avatar
thearch
Manager
Manager
Joined: 19 Feb 2005
Posts: 212
Own Kudos [?]: 69 [0]
Given Kudos: 0
Location: Milan Italy
Send PM
Re: S is the product of a list of consecutive integers from 1 to [#permalink] New post   31 May 2006, 10:48
yeah D it is

because 24/5=4 -> 4 multiples of 5
and 24/2=12 -> more than 4 multiples of 5
User avatar
tapan22
Manager
Manager
Joined: 29 Sep 2005
Posts: 77
Own Kudos [?]: 2 [0]
Given Kudos: 0
Send PM
Re: S is the product of a list of consecutive integers from 1 to [#permalink] New post   31 May 2006, 10:51
Thanks M8 and thearch very elegant and simple explanations.
User avatar
Professor
Director
Director
Joined: 29 Dec 2005
Posts: 566
Own Kudos [?]: 176 [0]
Given Kudos: 0
Send PM
Re: S is the product of a list of consecutive integers from 1 to [#permalink] New post   31 May 2006, 11:17
tapan22 wrote:
Professor what was the approach you took to arrive at 4? Can you pls explain?


there are at least four 5's and 2's. so that makes 10^4.

1. 25/5 -1 = 4 (four) 5's
2. 24/2 = 12 (twelve) 2's.

so that makes 4 (four) 10's.



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
GMAT Club Bot
gmatclubot
Re: S is the product of a list of consecutive integers from 1 to [#permalink]
31 May 2006, 11:17
Moderator:
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions