Question

An example of the even number of terms in an arithmetic progression written in a symmetrical format is?

• A. $a-d,a+d,a+2d,a+4d$.
• B. $a-2d,a+d,a+2d,a+3d$.
• C. $a-3d,a-d,a+d,a+3d$.
• D. $a-2d,a-d,a,a+d,a+2d$.

Answer 1

Answer: (C)

$a-3d,a-d,a+d,a+3d$.

An example of even number of terms in an arithmetic progression written in a symmetrical format is $a-3d,a-d,a+d,a+3d$. Here $a-d$ and $a+d$ is written where $2d$ is added and subtracted from them to get the terms at the ends. Thus the correct answer is $c$.