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Between the numbers 2 and 20 ,   8 means are inserted, then their sum is

Options

  1. A88
  2. B44
  3. C176
  4. Dnone of these

Correct answer

A. 88

Step-by-step solution

2 ,   A 1 ,   A 2 ,   … A 8 ,   20 are in A . P . where A 1 ,   A 2 ,   … A 8 are 8 Arithmetic means between 2 and 20 . Using the property that the sum of all the means inserted between two numbers is equal to the product of the number of means and the AM of the first and last terms. So, A 1 + A 2 + . . . . + A 8 = 2 + 20 2 × 8 = 88

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