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Let a₁, a₂, a₃ be in AP such that a₁+a₅+a₁₀+a₁₅+a₂₀+a₂₅+a₃₀+a₃₄=300 What is a₁+a₅-a₁₀-a₁₅-a₂₀-a₂₅+a₃₀+a₃₄ equal to?

Options

  1. A0
  2. B25
  3. C125
  4. D250

Correct answer

A. 0

Step-by-step solution

Since, aligned & a₁+a₅-a₁₀-a₁₅-a₂₂-a₂₅+a₃₀+a₃₄ & =a₁+a₁+4 d-a₁-9 d-a₁-14 d-a₁-19 d & =a₁-24 d+a₁+29 d+a₁+33 d & =0 aligned

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