Question

How do you find the sum of the arithmetic sequence given a1=76, n=21,an=176?

Answer 1

There is a formula devised perfectly for this type of problem: `S_n = n/2(a + a_n)`

Explanation:

`S_21 = 21/2(76 + 176)`

`S_21 = 2646`

Therefore, the sum of the sequence is 2646.

Hopefully this helps!