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

Home > Numbers
Generalize (Posted on 2013-05-01) Difficulty: 3 of 5
Using only 4$ and 7$ bills, you could pay any integer number of dollars, greater than 17.
Prove it.

Given two coprime numbers a and b, what is the minimal number M(a,b) such that any amount greater or equal to M(a,b) can be expressed as p*a+q*b (p & q non-negative integers)?

How much is M(37,38)?

No Solution Yet Submitted by Ady TZIDON    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
re(2): part 1 solution, plus examples of M(x,y) | Comment 3 of 5 |
(In reply to re: part 1 solution, plus examples of M(x,y) by Charlie)

a*b-a-b+1 = (a-1)*(b-1), which I find is computationally easier

Edited on May 1, 2013, 8:01 pm
  Posted by Steve Herman on 2013-05-01 19:59:16

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

Search body:
Forums (45)
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

Copyright © 2002 - 2019 by Animus Pactum Consulting. All rights reserved. Privacy Information