Precalculus (6th Edition) Blitzer

Published by Pearson
ISBN 10: 0-13446-914-3
ISBN 13: 978-0-13446-914-0

Chapter 10 - Section 10.2 - Arithmetic Sequences - Exercise Set - Page 1059: 36



Work Step by Step

Formula to calculate the sum of an arithmetic sequence is: $S_n=\dfrac{n}{2}(a_1+a_n)$ ...(1) Here, $a_1: $ First term and $d=$ common difference Since, we have $d=a_2-a_1=19-7=12$ and $a_{25}=7+12(25-1)=295$ Then, our first (1) equation becomes: $S_{25}=\dfrac{25}{2}(7+295)=\dfrac{25}{2}(302)=3775$
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.