Squash tournament matches

Twelve players signed up for the squash tournament. Based on the lottery, they formed pairs, and in the first round, each pair played one match. The winners advanced to the second round, where they played each other one game at a time. How many matches were played in the tournament altogether?

Final Answer:

n =  21

Step-by-step explanation:

$$\begin{gathered} m=12/2=6 \\ n=m+\frac{m\cdot (m-1)}{2}=6+\frac{6\cdot (6-1)}{2}=21 \end{gathered}$$

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