If `(n+2)! = 60 xx (n-1)! `, find n. – InterviewSolution

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1.	If `(n+2)! = 60 xx (n-1)! `, find n.
Answer» We have `(n+2)! = 60 xx (n-1)! ` ` rArr (n+2)xx(n+1)xx nxx(n-1)! = 60 xx (n-1)! ` ` rArr (n+2)(n+1)n=60 ` ` rArr (n+2)(n+1)n= 5 xx 4 xx 3 ` [ writing 60 as product of 3 consecutive integers] ` rArr n=3. ` Hence,`n=3. `

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