Question:
Find the sum of each of the following infinite series :
$6+1.2+0.24+\ldots \ldots \infty$
Solution:
It is Infinite Geometric Series.
Here, a=6
$r=\frac{1.2}{6}=\frac{2}{10}=0.2$
The formula used: Sum of an infinite Geometric series $=\frac{\mathrm{a}}{1-\mathrm{r}}$
$\therefore$ Sum $=\frac{6}{1-0.2}=\frac{6}{0.8}=\frac{15}{2}$
Sum $=\frac{15}{2}$