1. The problem statement, all variables and given/known data A bag contains 4 black and 5 white balls from which 6 balls are drawn. Determine the number of ways in which at least 3 black balls can be drawn. The book has solved it as combination. 2. Relevant equations 3. The attempt at a solution When we are drawing say black ball, isn't it the probability of getting 3 black balls at least? Also will it be correct to number the black ball e.g B1, B2, B3 & B4, which I feel it to be of no sense.