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Spot a pattern 2

Algebra Level 3

What is the value of $1+\dfrac {2}{5^1}+\dfrac {3}{5^2} +\dfrac{4}{5^3} + \dfrac{5}{5^4} + \cdots ?$

\dfrac{5}{4}

\dfrac{1}{25}

\dfrac{25}{16}

\dfrac{16}{25}

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Excel in math and science

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by Rohit Udaiwal

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