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Precalculus

Course: Precalculus > Unit 9

Lesson 1: Geometric series
Math
Precalculus
Series
Geometric series
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Geometric series formula

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Problem

The common ratio of a geometric series is 3 and the sum of the first 8 terms is 3280.
What is the first term of the series?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
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