(a) In how many ways can you distribute 4 distinguishable balls among 6 indistinguishable boxes?
(b) In how many ways can you distribute 4 indistinguishable balls among 5 distinguishable boxes?
(a) There are 44 ways.
(b) There are 210 ways.
a - listfor(k, 0, 6, (4 nCr k))==(1, 4, 6, 4, 1, 0, 0)==16 ways - without restrictions.
b - [x + n - 1] C [n]==[5 + 4 - 1] C 4 ==70 ways - without restriction
