An urn contains 5 red marbles, 4 ***** marbles and 3 white marbles. Then the number of ways in which 4 marbles can be drawn so that at the most three of them are red is ....
The question does not mention that whether same **** marbles are distinct or identical. So, assuming they are distinct our required answer = 12C4 – 5C4 = 490 And, if same **** marbles are identical then required answer = (2 + 3 + 4 + 4) = 13
