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[Community Question] Algebra-Precalculus: Calculating a cumulative series

One of our user asked:

I could do this on a calculator but I thought there would be a more efficient way to do this than punching on my calculator the following:

$3.5 \cdot 1.03 + 3.5 \cdot 1.03^2 + 3.5 \cdot 1.03^3 + \ldots + 3.5 \cdot 1.03^{10}$

So basically,

$xy + xy^2 + xy^3 + ... + xy^{10}$

How can I simplify this to make it easier to calculate on a calculator?


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