Answer
The amount by which we multiply each time is called the common ratio of the sequence.
The general form of the geometric sequence is $a,ar,a{{r}^{2}},a{{r}^{3}},\cdots $.
And $r$ is the common ratio.
Work Step by Step
The geometric sequence is the sequence in which each term after the first is obtained by multiplying the preceding term by a fixed nonzero constant ($r$).
$a,ar,a{{r}^{2}},a{{r}^{3}},\cdots $.
Consider the sequence,
$1,2,4,8,16\ldots $
In the sequence given above, the common ratio between two consecutive term is constant.
For example,
$\begin{align}
& \frac{2}{1}=\frac{4}{2} \\
& =\frac{8}{4} \\
& =\frac{16}{8} \\
& =2
\end{align}$
So, 2 is the fixed nonzero common ratio.
