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Finding a Term of an Arithmetic Series

Date: 12/13/95 at 20:17:48
From: Rodrigo Loyola
Subject: math question

The fifth term of an arithmetic series is 16 and the sum of the first 10 
terms is 145.  Write the first three terms.

Date: 12/14/95 at 22:31:47
From: Doctor Ken
Subject: Re: math question


Here's a hint: we can think of our arithmetic series as this:
a, a+d, a+2d, a+3d, a+4d, a+5d, a+6d, ...

Now all we'd have to do is figure out what a and d are, and we'd 
know what the entire series is.  See if you can figure out a couple of 
equations (from your statement of the problem) that would let you 
find a and d.

Good luck!

- Doctor Ken,  The Geometry Forum

Associated Topics:
High School Sequences, Series

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