Sequences and SeriesDate: 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. -Doctor Jerry, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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