We were enjoying the recent nice weather in the garden at the Jolly Quizmaster and sat at the next table were some ladies from the local Tennis Club, enjoying some Prosecco and in quite high spirits.

Eventually, one of their number called Sarah came over to our table and with the preamble of "you all like a puzzle", she told us about the tournament that they had just played.

"We each played a single set against all the other players, with no tie breaks, and would you believe that we all won exactly the same number of sets. I started off by losing a set to love against Jane, but recovered from that, and in the end I had won precisely the same number of games that I had lost. Oddly enough, Lois also won the same number of games as she lost. Stranger still, half the games that I lost came in the one set - can you believe it? And the other peculiar thing was that no two sets that we played had the same number of games in them."

With that she turned to return to her fellow tennis players, and then sprung a question on us - "What was the score in the set that I played against Lois?"

For each player to have won the same number of sets there must have been an odd number of players. There can't have been three nor could there have been seven or more, so there were five players.

To lose at set 0-6 and then win as many games as she lost, she must have won two sets by 6-1 and 6-3, and since she lost half her games in one set she must have lost her fourth set 8-10.

Lois also won as many games as she lost and her score against Sarah must have been 1-6, 3-6 or 10-8, the three sets that Sarah played that were not against Jane.

Since no two sets had the same number of games there are no scores available to balance the first two.

Hence Lois beat Sarah 10-8.