MATHEMATICS · Multi-part · A Level · Mathematics · Sequences and series · Sequences and series
Problem
For an arithmetic progression, the sum of the first 15 terms is 690 and the sum of the first 25 terms is 1 900.
(i) Determine the first term and the common difference of the progression.
(ii) Hence, find the 35th term.
(iii) Calculate the sum of the first 40 terms.