If {}^n P_r = 30240 and {}^n C_r = 252,then t | vedclass

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(B) Given that,${}^n P_r = 30240$ and ${}^n C_r = 252$. We know that ${}^n P_r = {}^n C_r 	imes r!$. Substituting the values,we get $30240 = 252 	im

Vedclass · Accepted Answer

$(10, 5)$

Vedclass · Answer

(B) Given that,${}^n P_r = 30240$ and ${}^n C_r = 252$. We know that ${}^n P_r = {}^n C_r 	imes r!$. Substituting the values,we get $30240 = 252 	imes r!$. $r! = \frac{30240}{252} = 120$. Since $120 = 5!$,we have $r = 5$. Now,${}^n P_5 = 30240$. $n(n-1)(n-2)(n-3)(n-4) = 30240$. Testing values,for $n = 10$: $10 	imes 9 	imes 8 	imes 7 	imes 6 = 30240$. Thus,$n = 10$. Hence,the required ordered pair is $(10, 5)$.

If ${}^n P_r = 30240$ and ${}^n C_r = 252$,then the ordered pair $(n, r)$ is equal to

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