Could anyone please help me with making a start.... and a finish to this little exercise. Many thanks Nat. Four people A, B, C and D are to play in a small table-tennis tournament played on a simple knock-out basis: their names are drawn at random to play in two pairs, then the two winners play in the final. The probability that a player beats a player with a later letter is 2/3. All matches are independent. Find the probabilities that: 1) A wins the tournament 2) C and D meet in the final 3) B and C meet at some stage Must I use a tree diagram?