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Find the sum of the infinite geometric series.\newline4+85+1625+32125+4 + \frac{8}{5} + \frac{16}{25} + \frac{32}{125} + \newlineWrite your answer as an integer or a fraction in simplest form.\newline______

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Q. Find the sum of the infinite geometric series.\newline4+85+1625+32125+4 + \frac{8}{5} + \frac{16}{25} + \frac{32}{125} + \newlineWrite your answer as an integer or a fraction in simplest form.\newline______
  1. Identify terms and ratio: To find the sum of an infinite geometric series, we need to identify the first term aa and the common ratio rr of the series. The first term in this series is 44, and each subsequent term is multiplied by 85\frac{8}{5} divided by the previous term, which is 25\frac{2}{5}. So, the common ratio rr is 25\frac{2}{5}.
  2. Use sum formula: The sum of an infinite geometric series can be found using the formula S=a1rS = \frac{a}{1 - r}, where SS is the sum of the series, aa is the first term, and rr is the common ratio. We have a=4a = 4 and r=25r = \frac{2}{5}.
  3. Plug in values: Now we plug the values into the formula to calculate the sum: S=4125S = \frac{4}{1 - \frac{2}{5}}.
  4. Simplify denominator: Simplify the denominator: 125=5525=351 - \frac{2}{5} = \frac{5}{5} - \frac{2}{5} = \frac{3}{5}.
  5. Divide by denominator: Now, divide the first term by the simplified denominator: S=4(35)S = \frac{4}{\left(\frac{3}{5}\right)}.
  6. Multiply by reciprocal: To divide by a fraction, we multiply by its reciprocal. So, S=4×(53)S = 4 \times \left(\frac{5}{3}\right).
  7. Calculate final sum: Multiply the numerators and denominators: S=(4×5)/3=20/3S = (4 \times 5) / 3 = 20 / 3.

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