SOLUTION: A geometric progression has 6 terms. The first term is 192 and the common
ratio is 1.5. An arithmetic progression has 21 terms and common difference 1.5.
Given that the sum of al
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-> SOLUTION: A geometric progression has 6 terms. The first term is 192 and the common
ratio is 1.5. An arithmetic progression has 21 terms and common difference 1.5.
Given that the sum of al
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Question 1164237: A geometric progression has 6 terms. The first term is 192 and the common
ratio is 1.5. An arithmetic progression has 21 terms and common difference 1.5.
Given that the sum of all the terms in the geometric progression is equal to the
sum of all the terms in the arithmetic progression, find the first term and the last
term of the arithmetic progression. Answer by greenestamps(13198) (Show Source):
I will let you have the pleasure of doing the calculations yourself....
(1) Find the 6 terms of the geometric progression. A calculator should make it easy; or an excel spreadsheet. Or you might be able to do it with mental arithmetic.
(2) Find the sum of those 6 terms.
(3) Divide that sum by the number of terms in the arithmetic progression, 21. That will give you the average of all the terms in the arithmetic progression.
(4) In an arithmetic progression of 21 terms the 11th term is the average of all the terms. So you know the 11th term.
(5) Add 10 times the common difference to the 11th term to find the 21st (last) term; subtract 10 time the common difference from the 11th term to find the first term.
