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karniyax
nPr=3024,then how to calculate the value of r?
Same question asked here http://openstudy.com/updates/50df347fe4b0f2b98c87319f
\[^nP_r=\frac{n!}{(n-r)!}\]
find the highest prime factor number in the factors here we are having 3024 = 7*3*3*3 *2*2*2*2 either start from the leading prime factor or form consecutive sequence of the factors obtained
here we are having 3024 = 9*8*7*6
3024 = 9*8*7*6*5! /5!= 9!/(9-4)!