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If ""^(n)P(r) = 840 and ""^(n)C(r) = 35,...

If `""^(n)P_(r) = 840` and `""^(n)C_(r) = 35`, then r is equal to ………… .

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To solve the problem, we need to use the formulas for permutations and combinations. Given: - \( nP_r = 840 \) - \( nC_r = 35 \) We know the relationships between permutations and combinations: - \( nP_r = \frac{n!}{(n-r)!} \) ...
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