MATHEMATICS · Subjective · A Level · Mathematics · Sequences and series · Sequences and series
Problem
For a geometric progression with positive terms, the sum of the first five terms is 242 and the sum of the next five terms (that is, the 6th to 10th terms) is 1936.
(a) Express the sum of the 6th to 10th terms in terms of S5 and the common ratio r.
(b) Hence, determine the common ratio r.
(c) Find the first term a of the progression.
(d) Calculate the 10th term of the progression.