Raise both sides to [tex]\dfrac1{60}[/tex].
[tex]8313.81=3000\left(1+\dfrac r{12}\right)^{60}[/tex]
[tex]\implies8313.81^{1/60}=3000^{1/60}\left(\left(1+\dfrac r{12}\right)^{60}\right)^{1/60}[/tex]
[tex]\implies1.162=1.143\left(1+\dfrac r{12}\right)[/tex]
[tex]\implies r\approx0.1995[/tex]
