Запишите выражение в виде частного, используя черту дроби: a) (1/3 + 7) * 1/3 ; б) (8 - 6 1/4) * 1/4 ; в) (5/6 - 1/2) * 1/2 ; г) (3/10 + 3/100) * 1/100.

a) $$\left(\frac{1}{3} + 7\right) \cdot \frac{1}{3} = \frac{\frac{1}{3} + 7}{3} = \frac{\frac{1}{3} + \frac{21}{3}}{3} = \frac{\frac{22}{3}}{3} = \frac{22}{3} : 3 = \frac{22}{3} \cdot \frac{1}{3} = \frac{22}{9}$$

б) $$\left(8 - 6\frac{1}{4}\right) \cdot \frac{1}{4} = \left(8 - \frac{25}{4}\right) \cdot \frac{1}{4} = \frac{8 - \frac{25}{4}}{4} = \frac{\frac{32}{4} - \frac{25}{4}}{4} = \frac{\frac{7}{4}}{4} = \frac{7}{4} : 4 = \frac{7}{4} \cdot \frac{1}{4} = \frac{7}{16}$$

в) $$\left(\frac{5}{6} - \frac{1}{2}\right) \cdot \frac{1}{2} = \frac{\frac{5}{6} - \frac{1}{2}}{2} = \frac{\frac{5}{6} - \frac{3}{6}}{2} = \frac{\frac{2}{6}}{2} = \frac{2}{6} : 2 = \frac{2}{6} \cdot \frac{1}{2} = \frac{2}{12} = \frac{1}{6}$$

г) $$\left(\frac{3}{10} + \frac{3}{100}\right) \cdot \frac{1}{100} = \frac{\frac{3}{10} + \frac{3}{100}}{100} = \frac{\frac{30}{100} + \frac{3}{100}}{100} = \frac{\frac{33}{100}}{100} = \frac{33}{100} : 100 = \frac{33}{100} \cdot \frac{1}{100} = \frac{33}{10000}$$

Ответ: a) 22/9; б) 7/16; в) 1/6; г) 33/10000