1. The problem statement, all variables and given/known data Divide 20 students in 4 groups of 5 each. Find the number of ways of doing this? Also find how can these gropus be sent to 4 different schools? 3. The attempt at a solution I get both the answers as: 20C5*15C5*10C5*5C5 But my book gives two different answers for the above 2 different question. Help Please!