Maria Brown is a young tennis player who has shot to fame after defeating Sarah Knowels in three consecutive matches. In the fourth match, Sarah decided to serve left each time. Is this an optimal winning strategy for Sarah?

What will be an ideal response?

Tennis is an example of a zero-sum game. This is because one player's loss is the other player's gain and hence, the sum of their payoffs is zero. The optimal winning strategy to play such games is to choose randomly between alternative strategies. In this case, if Sarah decides to serve left each time, Maria will soon figure out Sarah's strategy and will not miss a serve. However, if Sarah behaves unpredictably and randomly chooses between serving to the left and to the right, Maria will not be able to figure out Sarah's strategy before the serve and is more likely to miss the serve.