Minimum matches in a single-elimination tournament with byes: An elimination tournament has 139 players. Some rounds may include a bye if there is an odd number. What is the minimum number of matches required to determine a single champion?
Aptitude
Permutation and Combination
Difficulty: Easy
Choose an option
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A136
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B137
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C138
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D139
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ENone of these
Answer
Correct Answer: 138
Explanation
Introduction / Context:In any single-elimination tournament (knockout), each match eliminates exactly one player. Regardless of how byes are assigned, to go from n players down to 1 champion, we must eliminate n − 1 players, which requires n − 1 matches.
Given Data / Assumptions:
- n = 139 entrants.
- Single-elimination; a bye is not a match and eliminates no one.
- Each match eliminates exactly one player.
Concept / Approach:
- Matches needed = total eliminations = n − 1.
Step-by-Step Solution:
Required matches = 139 − 1 = 138Verification / Alternative check:Construct any bracket: every non-champion loses exactly one match; count of losses equals number of matches. The champion has no loss. Thus total matches equals losers = 138.
Why Other Options Are Wrong:
- 136, 137 undercount; 139 overcounts by one.
Common Pitfalls:
- Thinking byes change the total count; they alter scheduling, not the total eliminations.
Final Answer:138