# How do I find the common ratio of a geometric sequence?

May 18, 2015

The common ratio of a geometric sequence, denoted by $r$ , is obtained by dividing a term by its preceding term

considering the below geometric sequence:
$4 , 20 , 100$ ...

we can calculate $r$ as follows:
1) $\frac{20}{4} = 5$
2) $\frac{100}{20} = 5$

so for the above mentioned geometric sequence the common ratio $r = 5$