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HSA.SSE.B.4 Tutor Intake — Geometric Series Formula

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Grade 9·10 problems·~15 min·Common Core Math - HS Algebra·standard·hsa-sse-b-4

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Concepts

Consider the geometric series $2 + 6 + 18 + 54$ .

What does the formula $S = \dfrac{a(1 - r^n)}{1 - r}$ compute for
this series?

The 4th term of the sequence ( $ar^3 = 54$ )

The sum of all 4 terms ( $2 + 6 + 18 + 54 = 80$ )

The common ratio ( $r = 3$ )

The number of terms ( $n = 4$ )