Mathematics 9709 · AS & A Level · Series

Series — practice question

The first nine terms of an arithmetic progression add to 117. The next four terms add to 91.
(main)[4]

Determine the first term and the common difference of the progression.

Worked solution & mark scheme

This 4-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Set up $117=\frac{9}{2}(2a+8d)$” …

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI