[tex]\displaystyle\bf\\3.24=\frac{~~~324^{(4}}{100}=\boxed{\bf\frac{81}{25}}\\\\\\5,(6)=\frac{56-5}{9}=\frac{51}{9}=\boxed{\bf\frac{17}{3}}\\\\\\3.(21)=\frac{321-3}{99}=\frac{~~~318^{(3}}{99}=\frac{106}{33}\\\\\\0,2(5)=\frac{25-2}{90}=\boxed{\bf\frac{23}{90}}[/tex]