MATHguide's Arithmetic Series Sum Formula Quizmaster
Review the Lesson | MATHguide homepage Updated February 19th, 2006

Status: Waiting for your answers.
Use the first 21 terms of the following arithmetic series for the problem below:

-14 - 12 - 10 - 8 - ...

What is the 21th term? a21 =
What is the sum of the first 21 terms? S21 =