Sub-topic 1
2025 · National One-Eighth
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Selecting committees of men and women using combinations, e.g. $\binom{m}{k}\binom{w}{l}$
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Sub-topic 2
2026 · National Quarterfinal
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Finding $n$ in $^{n}p_{3}=990$
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Sub-topic 3
2018 · National Preliminary
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Arrangements of the letters of $games$ with the vowels $a$ and $e$ together
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Sub-topic 4
2025 · National Quarterfinal
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Solving $^{n}p_{4}=8\times{}^{n}p_{3}$ for $n$
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Sub-topic 5
2023 · National One-Eighth
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Entering and leaving a stadium with $10$ gates, $6$ north and $4$ south
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Sub-topic 6
2021 · National Preliminary
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Four-digit numbers from the digits $1,2,3,4,5$ with and without repetition
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Sub-topic 7
2021 · National Quarterfinal
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Evaluating $^{10}c_{5}$
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Sub-topic 8
2023 · National Preliminary
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Arrangements of $square$ beginning with a consonant and ending with a vowel
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