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If $^{12} P_{r} =^{11} P_{6} + 6 \cdot^{11} P_{5}$ then r is equal to

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We know that r⋅n-1pr-1+ n-1 pr=11 pr ∴ 6⋅11P5+11P6=12P6 [Putting r=6,n=12 ] =12Pr=12P6⇒r=6 ∵6⋅11P5+11P6=12Pr (given)!

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If 12Pr=11P6+6⋅11P5 then r is equal to

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If $^{12} P_{r} =^{11} P_{6} + 6 \cdot^{11} P_{5}$ then r is equal to