The 4th term of an arithmetic progression is 7 and the 12th term is 31

MATHEMATICS · Single correct · A Level · Mathematics · Sequences and series · Sequences and series

Problem

The 4th term of an arithmetic progression is 7 and the 12th term is 31. What is the 20th term? (a) 58 (b) 55 (c) 39 (d) 61