Q1 of 176 Page 20

Find the sum of the following geometric progressions :

2, 6, 18, … to 7 terms

Common Ratio = r =


∴ 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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