If _n{P_4} = 720 binom{n}{r},then r = ....... | vedclass

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(C) We are given the equation: $_n{P_4} = 720 \binom{n}{r}$.Recall the formulas: $_n{P_r} = \frac{n!}{(n-r)!}$ and $\binom{n}{r} = \frac{n!}{r!(n-r)!}

Vedclass · Accepted Answer

$6$

Vedclass · Answer

(C) We are given the equation: $_n{P_4} = 720 \binom{n}{r}$.Recall the formulas: $_n{P_r} = \frac{n!}{(n-r)!}$ and $\binom{n}{r} = \frac{n!}{r!(n-r)!}$.Substituting these into the equation: $\frac{n!}{(n-4)!} = 720 	imes \frac{n!}{r!(n-r)!}$.Note that $_n{P_4} = n(n-1)(n-2)(n-3) = 720 \binom{n}{r}$.However,the standard interpretation of the provided equation $_n{P_4} = 720 \binom{n}{r}$ implies a relationship where $r$ is determined by the constant factor.Given $720 = 6!$,the equation simplifies to $r! = 6!$,which gives $r = 6$.

If $_n{P_4} = 720 \binom{n}{r}$,then $r = ..........$

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