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If the sum of the first 100 terms of an AP is -1 and the sum of the even terms lying in the first 100 terms is 1 , then

Options

  1. Acommon difference is 3 50
  2. Bfirst term is - 149 50
  3. Ccommon difference is 7 50
  4. Dfirst term is - 151 50

Correct answer

B. first term is - 149 50

Step-by-step solution

100 2 (x₁+x₁₀₀ )=-1 50 2 (x₁+d+x₁₀₀ )=1

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