$\text{a)}\frac{{225}^{\circ }}{{\sout{{360}^{\circ }}}^{{18}^{\circ }}}\cdot {\sout{100}}^5\%=\frac{{\sout{{225}^{\circ }}}^{25}}{{\sout{{18}^{\circ }}}^2}\cdot 5\%=\frac{125}{2}\%=62,5\%$

$\text{b)}\frac{16}{{\sout{50}}^1}\cdot {\sout{100}}^2\%=32\%$

$\text{c)}\frac{2}{3}\cdot 100\%=\frac{200}{3}\%=66\frac{2}{3}\%$