Question

An urn contains 9 balls, 2 of which are red, three are blue and four black. 3 balls are drawn from the urn at random each ball has equal chance of being included in three. What is the chance that:
1. All the 3 balls are black
2. Three balls are of different colour
3. One is red and other two are black
4. The 2 balls are of same colour and 3rd of different colour
5. The balls are of same colour
6. At least one is red
5. The balls are drawn in the order: red, black and blue

Answer 1

1:4/9 is the answer of first