7 Bag \(A\) contains 4 balls numbered 2, 4, 5, 8. Bag \(B\) contains 5 balls numbered 1, 3, 6, 8, 8. Bag \(C\) contains 7 balls numbered \(2,7,8,8,8,8,9\). One ball is selected at random from each bag.
- Event \(X\) is 'exactly two of the selected balls have the same number'.
- Event \(Y\) is 'the ball selected from bag \(A\) has number 4'.
- Find \(\mathrm { P } ( X )\).
- Find \(\mathrm { P } ( X \cap Y )\) and hence determine whether or not events \(X\) and \(Y\) are independent.
- Find the probability that two balls are numbered 2, given that exactly two of the selected balls have the same number.