1) 10 similar roses distributed among 3 girls(girls are different).
let the 3 girls be x,y,z such that x+y+z=10
= C(n+r-1,r-1)
=C(12,2) = 66
2)10 different roses distributed to 3 different girls.
(note : here the funda is to fix the non movable object : fix girls)
1st rose can be given in 3 ways.
2nd rose can be given in 3 ways.
.
.
10 roses can be given in 310 ways = 59049