6.1 Angles and Their Measure/51

${\frac {\pi }{2}}\cdot {\frac {180^{\circ }}{\pi }}={\frac {\cancel {\pi }}{2}}={\frac {2\pi }{\pi }}$

\frac{\cancel{2}\cdot \cancel{2}\cdot 2\cdot \cancel{3}\cdot \cancel{5}}{1}\cdot\frac{\pi}{\cancel{2}\cdot \cancel{2} \cdot \cancel{5} \cdot \cancel{3} \cdot 3}