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A student read common difference of an A. P. as -2 instead of 2 and got the sum of first 5 terms as -5 . Actual sum of first five terms is

Options

  1. A25
  2. B-25
  3. C-35
  4. D35

Correct answer

D. 35

Step-by-step solution

5 2 2 a +4(-2) =-5 2 a =6 Actual sum = 5 2 6+4(2) =35

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