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The common ratio in a geometric series is 4 and the first term is 3 .
Find the sum of the first 8 terms in the series.

The common ratio in a geometric series is 44 and the first term is 33 .\newlineFind the sum of the first 88 terms in the series.

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Q. The common ratio in a geometric series is 44 and the first term is 33 .\newlineFind the sum of the first 88 terms in the series.
  1. Identify Formula: Identify the formula for the sum of the first nn terms in a geometric series.\newlineThe sum of the first nn terms in a geometric series can be found using the formula:\newlineSn=a(1rn)/(1r)S_n = a \cdot (1 - r^n) / (1 - r), where SnS_n is the sum of the first nn terms, aa is the first term, rr is the common ratio, and nn is the number of terms.
  2. Plug Values: Plug the given values into the formula.\newlineWe are given the first term a=3a = 3, the common ratio r=4r = 4, and the number of terms n=8n = 8. So we substitute these values into the formula:\newlineS8=3×(148)/(14)S_8 = 3 \times (1 - 4^8) / (1 - 4)
  3. Calculate Power: Calculate the power of the common ratio.\newlineCalculate 484^8 to simplify the formula.\newline48=655364^8 = 65536
  4. Substitute Value: Substitute the value of 484^8 back into the formula.\newlineS8=3×(165536)/(14)S_8 = 3 \times (1 - 65536) / (1 - 4)
  5. Simplify Numerator: Simplify the numerator of the formula.\newlineCalculate 1655361 - 65536.\newline165536=655351 - 65536 = -65535
  6. Simplify Denominator: Simplify the denominator of the formula.\newlineCalculate 141 - 4.\newline14=31 - 4 = -3
  7. Divide to Find Sum: Divide the numerator by the denominator to find the sum of the first 88 terms.S8=3×(65535)(3)S_8 = \frac{3 \times (-65535)}{(-3)}
  8. Final Answer: Simplify the expression to find the final answer.\newlineS8=3×65535/3S_8 = 3 \times 65535 / 3\newlineS8=65535S_8 = 65535

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