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Paragraph: Let a , x , y , z , b be in AP , where x + y + z =15 . Let a , p , q , r , b be in HP , where p ⁻¹+ q ⁻¹+ r ⁻¹= 5 3 Question: What is the value of pqr?

Options

  1. A35/243
  2. B81 / 35
  3. C243/35
  4. DCannot be determined

Correct answer

C. 243/35

Step-by-step solution

Since a, p, q, r, b or 1, p , q , r , 9 are in H.P. aligned & 1 1+4 ~d =9 d=- 2 9 & 1 p =1- 2 9 = 7 9 p= 9 7 & 1 q = 7 9 - 2 9 = 5 9 q= 9 5 & & 1 r = 5 9 - 2 9 = 3 9 r= 9 3 & p q r = 243 35 aligned

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