The term of an arithmetic sequence,

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

Problem

The

12^{\text{th}}

term of an arithmetic sequence,

a_{12}

, is twice as large as the

4^{\text{th}}

term in the sequence,

a_{4}

. (a). Given

a_{14} = 27

, find the value of

a_{1}

. (b). Find the

20^{\text{th}}

partial sum of this sequence.