Question

Find the sum of the arithmetic series 31+37 +43 +49 +... where n=8,OA. 416B. 1668OC. 832D. 834Reset Selection

Answer 1

Given the question in the image, the following are the solution steps to answer the question.

STEP 1: Write the given details

`\begin{gathered} a_1=31 \\ n=8 \\ d=37-31=6 \end{gathered}`

STEP 2: Write the formula for finding sum of arithmetic series

STEP 3: Find the sum of the series

By substitution,

`\begin{gathered} S_8=(8)/(2)[2(31)+(8-1)6] \\ S_8=4(62+42) \\ S_8=4(104)=416 \end{gathered}`

Hence, the sum is 416