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If 1 / 4,1 / x, 1 / 10 are in HP, then what is the value of x ?

Options

  1. A5
  2. B6
  3. C7
  4. D8

Correct answer

C. 7

Step-by-step solution

4, x, 10 are m AP. aligned & 2 x=4+10 & x= 14 2 =7 aligned

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