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The harmonic mean H of two numbers is 4 and the arithmetic mean A and geometric mean G satisfy the equation 2 ~A + G ^2=27 . The two numbers are

Options

  1. A6,3
  2. B9,5
  3. C12,7
  4. D3,1

Correct answer

A. 6,3

Step-by-step solution

aligned & 2 ~A + AH =27 & ~A (2+4)=27 aligned aligned & A = 9 2 & a+b=9 & a b= AH =18 aligned a=3 and b=6 or a=6 and b=3

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