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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 x y z ?

Options

  1. A120
  2. B105
  3. C90
  4. DCannot be determined

Correct answer

B. 105

Step-by-step solution

On solving eq (1) & (2), we get (i) a=1 & b=9 a+4 d=9 d=2 (ii) a =9 & ~b =1 a +4 ~d =1 ~d =-2 . For a =1 & ~d =2 , x=3, y=5 & z=7 For a =9 & ~d =-2 , x=7, y =5 & z =3 x y z=7 5 3=105

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