Q2 of 28 Page 9

Find the sum of the following geometric progressions 2, 6, 18, … to 7 terms.

Common Ratio



= 3


∴ Sum of GP for n terms …(1)


⇒ a = 2 , r = 3 , n = 7


∴ Substituting the above values in (1) we get



⇒ 37 – 1


⇒ 2186


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