Question

Find the sum of the given infinite geometric series

3+1.8+1.08+...

Answer 1

i knw the formula is \[S \infty = \frac{ a_1 }{ 1-r }\] but don't know what r is or how to find it.

Answer 2

r is the common ratio between the terms,
like r= 2nd term/1st term = 3rd term / 2nd term
so, what will be r here ?

Answer 3

.6

Answer 4

is 1.8 / 3 = 1.08 /1.8 = 0.6 ?
if yes, then r= 0.6 is correct

Answer 5

okay so just 3/.4 then?

Answer 6

got it, thanks :)

Answer 7

yup. thats it

Answer 8

welcome ^-^
go through this when u have time ..
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