Jump to content


Welcome to BrainDen.com - Brain Teasers Forum

Welcome to BrainDen.com - Brain Teasers Forum. Like most online communities you must register to post in our community, but don't worry this is a simple free process. To be a part of BrainDen Forums you may create a new account or sign in if you already have an account.
As a member you could start new topics, reply to others, subscribe to topics/forums to get automatic updates, get your own profile and make new friends.

Of course, you can also enjoy our collection of amazing optical illusions and cool math games.

If you like our site, you may support us by simply clicking Google "+1" or Facebook "Like" buttons at the top.
If you have a website, we would appreciate a little link to BrainDen.

Thanks and enjoy the Den :-)
Guest Message by DevFuse
 

Photo
- - - - -

Ants On a Ruler


Best Answer bonanova, 19 January 2013 - 07:11 AM

You have a one meter ruler. We will drop 200 ants on to the ruler, each ant falling at a location along the ruler which is uniformly distributed. When an ant falls, it goes left or right with equal probability. When two ants bump into each other they reverse directions. Each ant moves along the string at a speed of 1 meter per minute. How long will it take for all the ants to fall off the ruler?


Hi sergyegi, and welcome to the Den.

Spoiler for looks like
Go to the full post


  • Please log in to reply
4 replies to this topic

#1 sergyegi

sergyegi

    Newbie

  • Members
  • Pip
  • 1 posts

Posted 19 January 2013 - 02:24 AM

You have a one meter ruler. We will drop 200 ants on to the ruler, each ant falling at a location along the ruler which is uniformly distributed. When an ant falls, it goes left or right with equal probability. When two ants bump into each other they reverse directions. Each ant moves along the string at a speed of 1 meter per minute. How long will it take for all the ants to fall off the ruler?


  • 0

#2 bonanova

bonanova

    bonanova

  • Moderator
  • PipPipPipPip
  • 5918 posts
  • Gender:Male
  • Location:New York

Posted 19 January 2013 - 07:11 AM   Best Answer

You have a one meter ruler. We will drop 200 ants on to the ruler, each ant falling at a location along the ruler which is uniformly distributed. When an ant falls, it goes left or right with equal probability. When two ants bump into each other they reverse directions. Each ant moves along the string at a speed of 1 meter per minute. How long will it take for all the ants to fall off the ruler?


Hi sergyegi, and welcome to the Den.

Spoiler for looks like

  • 0
The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#3 Anza Power

Anza Power

    Junior Member

  • Members
  • PipPip
  • 80 posts

Posted 19 January 2013 - 11:33 AM

 

You have a one meter ruler. We will drop 200 ants on to the ruler, each ant falling at a location along the ruler which is uniformly distributed. When an ant falls, it goes left or right with equal probability. When two ants bump into each other they reverse directions. Each ant moves along the string at a speed of 1 meter per minute. How long will it take for all the ants to fall off the ruler?

Hi sergyegi, and welcome to the Den.

Spoiler for looks like

 


Edited by Anza Power, 19 January 2013 - 11:33 AM.

  • 0

#4 TimeSpaceLightForce

TimeSpaceLightForce

    Senior Member

  • Members
  • PipPipPipPip
  • 677 posts
  • Gender:Male

Posted 19 January 2013 - 06:39 PM

Spoiler for

 


  • 0

#5 TimeSpaceLightForce

TimeSpaceLightForce

    Senior Member

  • Members
  • PipPipPipPip
  • 677 posts
  • Gender:Male

Posted 19 January 2013 - 10:20 PM

Spoiler for shortest possible time


  • 0




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users