I need to find the sum of the arithmetic sequence 3, 9, 15…, if there are 24 terms

Cortez Clarke

Cortez Clarke

Answered question

2022-11-18

I need to find the sum of the arithmetic sequence 3, 9, 15…, if there are 24 terms

Answer & Explanation

motylowceyvy

motylowceyvy

Beginner2022-11-19Added 19 answers

We must first find the common difference, r.
r = t 2 - t 1
r=9−3
r=6
Now, we can use the formula s n = n 2 ( 2 a + ( n - 1 ) d )
n = 24
a = 3
r = 6
s 24 = 24 2 ( 2 ( 3 ) + ( 24 - 1 ) 6 )
s 24 = 12 ( 6 + 138 )
s 24 = 12 ( 144 )
s 24 = 1728

Do you have a similar question?

Recalculate according to your conditions!

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?