Question

Find the value of r for an infinite geometric series with S=16 and a_1=4?

Answer 1

`r=3/4`

Explanation:

`S= a_1/(1-r)`

`16= 4/(1-r)`

`16(1-r)= 4`

`16-16r= 4`

`16r=12`

`r= 12/16= 3/4`

`r=3/4`

Hope that helps.