Q179
ArithmeticPermutations, Combinations & Probability
In a chess tournament each of six players will play every other player exactly once. How many matches will be played in the tournament?
- a.12
- b.15
- c.30
- d.72
Answer: (B) 15
The number of matches = $\binom{6}{2} = \frac{6 \times 5}{2} = 15$. This is the number of ways to choose 2 players from 6 for each unique pairing. Alternatively, using the formula $\frac{n(n-1)}{2} = \frac{6 \times 5}{2} = 15$.