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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 are given two equations involving permutations and combinations: 1. \( nP_r = 840 \) 2. \( nC_r = 35 \) We need to find the value of \( r \). ### Step-by-Step Solution: ...
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