3. In how many ways can you place 4 red balls, 3 yellow balls, 6 black balls, 2 blue balls, and l orange ball in a row? Given : Solution: help po ty :)
Solution : We have to arrange 12 balls, out of which 3 are of one kind, 4 are of second kind and 5 are of third kind. <br> Required number of arrangements `=(12!)/((3!) xx(4!) xx (5!))`.