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

 It is currently 04 May 2015, 23:50

### 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

# If n is a positive integer and 10^n is a factor of m, what

Author Message
TAGS:
Manager
Status: Working hard to score better on GMAT
Joined: 02 Oct 2012
Posts: 91
Location: Nepal
Concentration: Finance, Entrepreneurship
GPA: 3.83
WE: Accounting (Consulting)
Followers: 0

Kudos [?]: 75 [1] , given: 23

If n is a positive integer and 10^n is a factor of m, what [#permalink]  26 May 2013, 07:56
1
KUDOS
1
This post was
BOOKMARKED
00:00

Difficulty:

85% (hard)

Question Stats:

40% (01:58) correct 60% (01:22) wrong based on 106 sessions
If n is a positive integer and 10^n is a factor of m, what is the value of n?

(1) m is the product of the first positive 40 numbers .
(2) n > 8*m/40!
[Reveal] Spoiler: OA

_________________

Do not forget to hit the Kudos button on your left if you find my post helpful.

Last edited by Bunuel on 26 May 2013, 08:16, edited 1 time in total.
Edited the question.
Math Expert
Joined: 02 Sep 2009
Posts: 27215
Followers: 4229

Kudos [?]: 41036 [4] , given: 5654

Re: If n is a positive integer and 10n is a factor of m, what is [#permalink]  26 May 2013, 08:18
4
KUDOS
Expert's post
2
This post was
BOOKMARKED
If n is a positive integer and 10^n is a factor of m, what is the value of n?

Given that $$m=10^n*k$$ for some positive integer k.

(1) m is the product of the first positive 40 numbers --> $$m=40!$$ --> $$40!=10^n*k$$. The number of trailing zeros of 40! is 40/5+40/25=8+1=9 (check here: everything-about-factorials-on-the-gmat-85592.html). So, 40! ends with 9 zeros, which means that n could be from 1 to 9, inclusive. Not sufficient.

(2) n > 8*m/40!. Clearly not sufficient.

(1)+(2) From (1) $$m=40!$$, thus from (2) $$n>\frac{8*40!}{40!}=8$$. Since from (1) we also have that $$1\leq{n}\leq{9}$$, then n=9. Sufficient.

Similar question to practice: if-d-is-a-positive-integer-and-f-is-the-product-of-the-first-126692.html

Hope it helps.
_________________
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 4772
Followers: 296

Kudos [?]: 52 [0], given: 0

Re: If n is a positive integer and 10^n is a factor of m, what [#permalink]  27 Jan 2015, 09:45
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: If n is a positive integer and 10^n is a factor of m, what   [#permalink] 27 Jan 2015, 09:45
Similar topics Replies Last post
Similar
Topics:
3 If n is a positive integer and k=5.1*10^n, what is the value 9 21 May 2011, 09:08
If n is a positive integer and p = 3.021 10n, what is the 6 24 Apr 2011, 08:22
7 If n is a positive integer and k = 5.1 x 10^n , what is the 3 09 Mar 2011, 06:52
if n is a positive integer and k=5.1*10^n, what is the value 3 17 Feb 2008, 17:41
If n is a positive integer and k=5.1*10^n , what is the 4 03 Jun 2005, 11:31
Display posts from previous: Sort by