Hair Problem
What is the probability that, at least two people in the world have exactly same number of hairs ?
Labels: logic, outside-the-box
posted by Rajesh Lal at
8:16 PM
Thursday, February 26, 2009
Links
Search
Share
- Tom Chrome Extension
- ToM @ Twitter
- MeeT ToM
- Daily Tricks Widget
- Vista Gadget 1.5
- iPhone Widget
- Windows XP Widget
- Google Toolbar Button
- Suggestions
Favorite Links
- Vista Sidebar Gadgets
- Widgets for Web 2.0
- C Sharp Tricks
- Interview Information
- Illustrator - Elar Alexander
Bookmark Us
Previous Posts
- Tom, Dick and Harry
- Triangle Trio
- Birthday Puzzle
- The Value
- Through the Playing Card
- T, V or Y
- Areas of Circles
- From A to B
- Horse Racing
- Seven Seconds
8 Comments:
It is a very good probability that 2 people will have the exact same numbers of hair on their heads. One of the most common styles for men is being bald. Bald = 0 hairs.
However if you meant hairs on the entire body, then that probability would be very different
It's a certainty due to the pigeon hole principal.
100%
there are at least 6billion people in the world, much more than the possible number of hairs on a head
100%
Some people in this world actually share a head.
Consider the N numbers b1 = (a1) mod(N), b2 =(a1 + a2) mod(N), b3 = (a1+a2+a3) mod(N), ..., bN = (a1 + ... + aN) mod(N). If one of these numbers is zero, then we are done. Otherwise, only the N-1 numbers 1, 2, ..., N-1 are represented in this list, and so two of them must be the same, bi = bj (say i < j). This would then imply that (ai+1 + ... + aj) mod(N) = 0
The number of hairs on either your head or your body is not a static number. It's a dynamic number. We shed and regrow hair constantly throughout the day. By the time you counted the hairs on a persons hiar, the number would already be inaccurate.
100%
Bald people have no hair
100%
you cant count the amount of hairs on your head... i tried...lol
Post a Comment
Links to this post:
Create a Link
<< Home