The first term of an arithmetic progression is and the common difference is

MATHEMATICS · Subjective · CBSE · Mathematics · Arithmetic Progressions · Arithmetic Progressions

Problem

The first term of an arithmetic progression is

8

and the common difference is

3

. (a) If the sum of the first

n

terms is

215

, find the value of

n

. (b) Using the same progression, calculate the

15

th term.