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Question
Evaluate: `("n"!)/("r"!("n" - "r"!)` For n = 12, r = 12
Solution
n = 12, r = 12
∴ `("n"!)/("r"!("n" - "r"!)) = (12!)/(12!(12 - 12)!) =(12!)/(12! 0!)`
= 1 ...[∵ 0! = 1]
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