- #1

CStudent

- 15

- 0

* How many ways we can insert 16 similar balls to 4 drawers such that in every drawer we have at least 3 balls?

So I know we have to insert at first 3 balls to every drawer and the remainder is 4 balls.

But how can I calculate the amount of possibilities to insert 4 balls to 4 drawers without any limit?

Thanks.