Question

Find the sum of the first 40 terms of a geometric sequence where the first term is 16 and the common ratio is 1.1

Answer 1

Given:

`a=16\text{ ; }r=1.1;S_{n\text{ }}=\text{?}`
`S_n=(a(r^n-1))/(r-1)`
`S_n=(16(1.1^(40)-1))/(1.1-1)`
`S_n=(16(45.26-1))/(0.1)`
`S_n=(16(44.26))/(0.1)`
`S_n=(708.16)/(0.1)`
`S_n=7081.6`