Question

Use the geometric series formulas to find the sum of the geometric series.

0.8 + 0.64 + 0.512 + ⋯ + 0.32768

Answer 1

2.68928

Explanation:

The sum of geometric series formulas is

`S_(n)=(a_(1)(1-r^(n) ))/(1-r)`

Where
`S_(n)` is the Sum,
`a_(1)` is the first member of the series, r the common ratio (in this case 0.8) and n is the number of terms.

Using the formula:

`S_(n)=(0.8(1-0.8^(5) ))/(1-0.8)`

Then

S_{n}=2.68928