SOLUTION: The sum of an arithmetic series is 100 times the value of its first term, while the last term is 9 times the first term. Calculate the number of terms in the series if the first te
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-> SOLUTION: The sum of an arithmetic series is 100 times the value of its first term, while the last term is 9 times the first term. Calculate the number of terms in the series if the first te
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Question 1134943: The sum of an arithmetic series is 100 times the value of its first term, while the last term is 9 times the first term. Calculate the number of terms in the series if the first term is not equal to zero. Found 2 solutions by josmiceli, greenestamps:Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! Formula for sum:
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29 terms
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check:
I used instead of
That's the error, I think. Definitely get
a 2nd opinion on this.
The other tutor mistakenly used the formulas for geometric series instead of arithmetic series....
The last term is 9 times the first term, so we can call the first and last terms a and 9a.
The average of the terms in an arithmetic sequence is the average of the first and last terms, so the average of the terms in the sequence is 5a.
The sum of the terms of an arithmetic series is the average of the terms, multiplied by the number of terms. Since the sum of the terms is 100 times the first term, the number of terms n can be found with
