Question

What is the sum of the arithmetic sequence 8, 15, 22 ..., if there are 26 terms? (6 points)A 2,483B 2,485C 3,487D 3,489

Answer 1

The correct option is A. 2483

Step-by-step explanation

Given:

8, 15, 22 .........

First, find the common difference (d) = 15 - 8 = 7

We can calculate the sum of the arithmetic sequence using the formula below:

`Sn=(n)/(2)\lbrack(2a+(n-1)d\rbrack`

Where a is the first term, n is the number of term and d is the common difference.

n = 26 a = 8 and d=7

Substitute the values into the formula and evaluate.

`S_(26)=(26)/(2)\lbrack2(8)+(26-1)7\rbrack`
`=13\lbrack16+25(7)\rbrack`
`=13\lbrack16+175\rbrack`
`=13(191)`
`=2483`

Hence, the correct option is A. 2483