SOLUTION: solve the equation P(n,5) = 20P(n,3) for n

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Question 771267: solve the equation P(n,5) = 20P(n,3) for n
Answer by oscargut(2103) About Me  (Show Source):
You can put this solution on YOUR website!
P(n,5) = 20P(n,3) for n
n!/(n-5)! = 20n!/(n-3)!
1/(n-5)! = 20/(n-3)!
(n-3)! = 20(n-5)!
(n-3)(n-4)= 20
n = 8
Answer: n=8
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