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If the first term of an AP is 2 and the sum of the first five terms is equal to one-fourth of the sum of the next five terms, then what is the sum of the first ten terms?

Options

  1. A-500
  2. B-250
  3. C500
  4. D250

Correct answer

B. -250

Step-by-step solution

Let common difference =d . Then, sum of first 5 terms = Sum of next 5 terms 4 aligned & 1 2 5(4+4 d)= 1 4 1 2 5 (2+5 d)+4 d & 4 4(1+d)=4+14 d aligned d=-6 . Sum of first ten terms= 1 2 10 (2 2+9(-6) =-250.

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