Question 13

How many terms of G.P. 3, 3^{2}, 3^{3}, … are needed to give the sum 120?

Answer

The given G.P. is 3, 3^{2}, 3^{3}, …

Let *n* terms of this G.P. be required to obtain the sum as 120.

Here, *a* = 3 and *r* = 3

∴

∴ *n* = 4

Thus, four terms of the given G.P. are required to obtain the sum as 120.

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Riya prasad
2021-10-30 07:22:14

Very good ðð

Sameer sharma
2019-11-04 09:10:53

Thanks for solving the question

- NCERT Chapter