Tennis tournament

Eight tennis players took part in the tennis tournament. They were divided into two groups of four. In each group, everyone played each other once. The winner of the first group played the winner of the second group in the final. They did not play other matches. Find out how many matches were played together in this tournament.

Final Answer:

n =  13

Step-by-step explanation:

$$\begin{gathered} n_1=3+2+1=6 \\ n=2\cdot n_1+1=2\cdot 6+1=13 \end{gathered}$$

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