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If a denotes the number of permutations of (x+2) things taken all at a time,b the number of permutations of x things taken 11 at a time and c the number of permutations of (x-11) things taken all at a time such that a=182bc,then find the value of x.
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2 Answers
62a = (x+2)!
b= xP11
c= (x-11)!
(x+2)(x+1)x! = 182 (x-11)! x! / (x-11)!
(x+2)(x+1) = 182
x=12