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

Home > Numbers
A Cube Root And Multiple Puzzle (Posted on 2007-08-10) Difficulty: 3 of 5
Determine the largest possible value of B such that it is a multiple of all positive whole numbers less than ³√B.

See The Solution Submitted by K Sengupta    
Rating: 4.0000 (3 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution Solution | Comment 4 of 6 |
Consider x,x-1,x-2,x-3
If x is a multiple of 3, then LCM of these = x*(x-1)*(x-2)*(x-3)/6
Otherwise, LCM = x*(x-1)*(x-2)*(x-3)/2
This should be less than (x+1)³.
Case1: x≤12
Case2: x<8
x can take values {1,2,3,4,5,6,7,9,12}
But checking for x=9,12 gives no solution.
For x=7, LCM=420<8³.
Largest Possible Value of B=420.

  Posted by Praneeth on 2007-08-14 06:46:51
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 (3)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information