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If the harmonic mean of 60 and x is 48 , then what is the value of x ?

Options

  1. A32
  2. B36
  3. C40
  4. D44

Correct answer

C. 40

Step-by-step solution

If the Harmonic mean of 60 and x is 48 , then aligned & 2 48 = 1 60 + 1 x & 1 x = 2 48 - 1 60 = 1 12 [ 2 4 - 1 5 ] & 1 x = 1 12 10-4 20 = 6 12 20 & x=40 aligned

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