All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Probability
Die Order (Posted on 2013-01-04) Difficulty: 3 of 5
A single die is rolled four times.

What is the probability that the numbers that come up will be in ascending order (not necessarily strictly ascending, but never a lower number after a higher)?

Intended to be solved without a computer.

See The Solution Submitted by Charlie    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution No Subject | Comment 4 of 7 |

a(1)= 6  ;

 a(2)=21  ;

a(3)=56 ;

>  a(4)=126   ; 

a(5)= 252  ;

......

                   a(n)=combin(n+5,n)

.......................

p(4)=126/(6^4)= 7/72

Edited on January 4, 2013, 6:56 pm
  Posted by Ady TZIDON on 2013-01-04 18:50:51

Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (1)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2017 by Animus Pactum Consulting. All rights reserved. Privacy Information