Основы электротехники, решите

[tex] - 3 \frac{1}{2} +7 \frac{1}{3} = - \frac{7}{2} + \frac{22}{3} = \\ - \frac{21}{6} + \frac{44}{6} = \frac{44}{6} - \frac{21}{6} = \frac{23}{6} = 3 \frac{5}{6} [/tex][tex] - \frac{2}{3} + 2 \frac{1}{3} = 2 \frac{1}{3} - \frac{2}{3} = \\ \frac{7}{3} - \frac{2}{3} = \frac{5}{3} = 1 \frac{2}{3} [/tex][tex]6.3 - 2.8 = 3.5[/tex][tex]7.2 + ( - 0.8) =7.2 - 0.8 = 6.4[/tex][tex]3.8 - 4.9 = - 1.1[/tex][tex]2.01 - 3.71 = 1.7[/tex][tex] - 1.2 + 6.5 = 6.5 - 1.2 = 5.3[/tex][tex]2.8 - 4.9 = - 2.1[/tex][tex]3.2 - 2 \frac{4}{15} = \frac{32}{10} - \frac{30}{15} = \\ \frac{16}{5} - \frac{10}{5} = \frac{6}{5} = 1 \frac{1}{5} [/tex]