MATHEMATICS · Multi-part · GCSE · Further Mathematics · Sequences and Series · Sequences and Series
Problem
A sequence has its 4th term equal to 12, its 10th term equal to 24 and its 20th term equal to 45.
(i) Assuming the sequence is an arithmetic progression, find the first term and the common difference using the 4th and 10th terms.
(ii) Verify whether the given 20th term is consistent with your result in part (i).
(iii) State, with reasons, whether the three given terms can belong to one and the same arithmetic progression.