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If n!, 3 (n!) and (n+1)! Are in GP, then the value of n will be

Options

  1. A3
  2. B4
  3. C8
  4. D10

Correct answer

C. 8

Step-by-step solution

n!, 3(n!) and (n+1)! are in G.P. [3(n!)]^2=n! (n+1)! aligned 9(n!)(n!) & =n!(n+1) n! 9 & =n+1 aligned n=8 .

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