Find the sum of the first five terms of the G.P 2,6, 18 ....

  • A 484
  • B 243
  • C 242
  • D 130
  • E 121

The correct answer is C. 242

\(S_{n} = \frac{a(r^n - 1)}{r - 1}\)

a = 2; r = 6/2 = 3.

\(S_{5} = \frac{2(3^5 - 1)}{3 - 1}\)

= \(243 - 1 = 242\)

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