View more

View more

View more

### Image of the Day Submit

IOTD | Top Screenshots

### The latest, straight to your Inbox.

Subscribe to GameDev.net Direct to receive the latest updates and exclusive content.

# discrete math problem

Old topic!

Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.

### #1thuned  Members

Posted 03 August 2001 - 04:16 PM

i have a hw problem that i have problem solving. w + x+ y + z = 12 how many nonnegative interger solutions are there? well, using the "r-combinations w/ repitition allowed" rule u get 3 seperators so the answer would be C(12+3,12) -> C(15,12) ok, here''s what i have the problem in: w needs to be 0 <= w <= 4, meaning it can only be 0,1,2,3,or 4 0<=x<=5 0<=y<=8 0<=z<=9 having a hard time with this... please help

### #2thuned  Members

Posted 04 August 2001 - 02:19 PM

nm, i got it.

and if any1 cares, this is how i did it.
total poss: C(15,12) = 455
subtract the ones outside each range for each variable
455-120-84-20-10
then since the subtracted #''s overlap by 4, u add 4
resulting in 225.

Old topic!

Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.