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Question
Find n, if `""^23"C"_(3"n") = ""^23"C"_(2"n" + 3)`
Solution
`""^23"C"_(3"n") = ""^23"C"_(2"n" + 3)`
∴ 3n = 2n + 3 ...(∵ nCx then x = y)
∴ 3n – 2n = 3
∴ n = 3
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