Algebra 2 (1st Edition)

Published by McDougal Littell
ISBN 10: 0618595414
ISBN 13: 978-0-61859-541-9

Chapter 12 Sequences and Series - 12.1 Define and Use Sequences and Series - 12.1 Exercises - Skill Practice - Page 799: 58



Work Step by Step

The sum is the sum of the first 20 natural numbers. Using the trick of Gauss, $20+1=21$ $19+2=21$ $18+3=21$ $...$ $11+10=21$ (all 20 numbers are used up) Ten pairs, each adding to 21, total to $10\times 21=210$
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.