NEW HERE? LEARN MORE
closeclose
Last visit was: 26 Apr 2024, 09:22 It is currently 26 Apr 2024, 09:22
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

[#43] 2 Min. Challenge : Snow White

User avatar
Praetorian
CEO
CEO
Joined: 15 Aug 2003
Posts: 2876
Own Kudos [?]: 1649 [0]
Given Kudos: 781
Send PM
[#43] 2 Min. Challenge : Snow White [#permalink] New post   10 May 2004, 15:15
Halle. , Anand, Paul, please wait a while before replying. you are all great in math. but if you wait and let other guys answer first, i think it would help them better. IF they do problems wrong, kindly help them out. thanks :) I hope others participate :oops:

Code: md.
Level : Advanced (again, try to do it under 2 Mins.)


Starting January 1, the first dwarf visits Snow White every day. The second dwarf visits Snow White on January 2 and every second day therafter. The pattern continues for each of the seven dwarfs (i.e., the seventh dwarf visits Snow White on January 7 and every seventh day thereafter). What is the total number of dwarf visits up to and including the first day when all seven dwarfs visit Snow White?

a. 28
b. 42
c. 105
d. 420
e. 1089



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
sachy
Intern
Intern
Joined: 06 May 2004
Posts: 10
Own Kudos [?]: [0]
Given Kudos: 0
Location: Toronto
Send PM
Re: [#43] 2 Min. Challenge : Snow White [#permalink] New post   10 May 2004, 19:23
420 is my answer (less than 2 min)

its LCM of 1,2,3...7
User avatar
Emmanuel
Manager
Manager
Joined: 07 May 2004
Posts: 104
Own Kudos [?]: 23 [0]
Given Kudos: 0
Location: Ukraine, Russia(part-time)
Send PM
Re: [#43] 2 Min. Challenge : Snow White [#permalink] New post   10 May 2004, 23:56
Praetorian wrote:
Halle. , Anand, Paul, please wait a while before replying. you are all great in math. but if you wait and let other guys answer first, i think it would help them better. IF they do problems wrong, kindly help them out. thanks :) I hope others participate :oops:

Code: md.
Level : Advanced (again, try to do it under 2 Mins.)


Starting January 1, the first dwarf visits Snow White every day. The second dwarf visits Snow White on January 2 and every second day therafter. The pattern continues for each of the seven dwarfs (i.e., the seventh dwarf visits Snow White on January 7 and every seventh day thereafter). What is the total number of dwarf visits up to and including the first day when all seven dwarfs visit Snow White?

a. 28
b. 42
c. 105
d. 420
e. 1089


The first day, when all dwarfs visit Snow White is n :: 1, 2, 3, 4, 5, 6, 7.

n = 420.

Total # = 420 + 420/2 + 420/3 + 420/4 + 420/5 + 420/6 + 420/7 = 1089.
User avatar
anandnk
Director
Director
Joined: 30 Oct 2003
Posts: 899
Own Kudos [?]: 373 [0]
Given Kudos: 0
Location: NewJersey USA
Send PM
Re: [#43] 2 Min. Challenge : Snow White [#permalink] New post   Updated on: 11 May 2004, 10:27
I second Emmanuel's explanation.
On 420th day all of them meet the Snowwhite. I wonder why cant the first dwarf live with her. :shock: :roll:

Originally posted by anandnk on 11 May 2004, 10:19.
Last edited by anandnk on 11 May 2004, 10:27, edited 1 time in total.
User avatar
sachy
Intern
Intern
Joined: 06 May 2004
Posts: 10
Own Kudos [?]: [0]
Given Kudos: 0
Location: Toronto
Send PM
Re: [#43] 2 Min. Challenge : Snow White [#permalink] New post   11 May 2004, 10:22
I didn't pay attention to the question - so I am wrong. I stopped after finding first day when all dwarfs would visit together. :cry:
thats usually where I mess up things(paying not enough attn to questions).
avatar
al1234
Intern
Intern
Joined: 10 May 2004
Posts: 5
Own Kudos [?]: [0]
Given Kudos: 0
Send PM
Re: [#43] 2 Min. Challenge : Snow White [#permalink] New post   11 May 2004, 11:34
The question was a bit misleading :
According to my interpretation all Dwarfs meet SnowWhite at least once till Sunday 7th of Jan. Where the number of visits are:
7/1+[7/2]+[7/3]+[7/4]+[7/5]+[7/6]+7/7 = 7+3+2+1+1+1+1 = 16
unfortunately this number was not among the choices. :cry:
User avatar
Praetorian
CEO
CEO
Joined: 15 Aug 2003
Posts: 2876
Own Kudos [?]: 1649 [0]
Given Kudos: 781
Send PM
Re: [#43] 2 Min. Challenge : Snow White [#permalink] New post   11 May 2004, 14:14
I wish more new guys participate. :oops:

The answer is E.

Nice work emmanuel. sachy, its ok, just write down the problem that you get wrong somewhere and write some notes for yourself.

Let N=number of days until all 7 dwarfs visit. Then N is the smallest integer that is divisible by 1,2,...7. So N=3· 4· 5· 7=420. In these 420 days, Dwarf #1 visits 420 times, #2 visits 210 times, #3 visits 140 times, #4 visits 105 times, #5 visits 84 times, #6 visits 70 times, and #7 visits 60 times.

al1234, please let us know if you need help.

Sincerely
Praet



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: [#43] 2 Min. Challenge : Snow White [#permalink]
11 May 2004, 14:14
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