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Sequences and Series

Date: 4/27/96 at 16:39:46
From: Anonymous
Subject: Sequences and Series

Between two numbers whose sum is 5.5, k arithmetic means
are to be inserted.  If the sum of the means is 21 more than
the number of means, determine the number of means.

Date: 7/29/96 at 13:40:37
From: Doctor Jerry
Subject: Re: Sequences and Series

The given statement directly implys that
 (1)  a+b=11/2
 (2)  a+(k+1)d=b
 (3)  k(a-1)+d(k+1)*k/2=21

If (1) and (2) are solved for a and b in terms of k and d and the 
results are substituted in (3), we find k=12.

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Associated Topics:
High School Calculus

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