Christopher W. answered • 05/17/19
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If you have the first term, the common ratio, and the number of terms in the series (sum) then you may use the following calculator to determine the sum. https://www.mathportal.org/calculators/sequences-calculators/geometric-sequences-calculator.php
Christopher W.
Hello. Do they tell you the last term in the series? If so, you can use that as "an" in the formula an = a1 * r ^ (n-1) to solve for n. "n" is the number of terms in the series. "r" is the common ratio, and "a1" is the first term.
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05/18/19
Eboni R.
What if you aren't given the number of terms in the series?05/17/19