## Precalculus (6th Edition) Blitzer

The general formula for finding ${{a}_{n}}$ is given by; ${{a}_{n}}\text{ }={{a}_{1}}\text{ }{{\left( r \right)}^{n-1}}$ Here, $r$ is the common ratio. Compare the equation with ${{a}_{n}}\text{ }=\text{ }3{{\left( 0.5 \right)}^{n-1}}$. We get $r=\frac{1}{2}$ Hence, the given statement is true.