Вариант 1. Задание 2: Выполните действия: a) \(\frac{1}{3}\) + \(\frac{2}{5}\), б) \(\frac{5}{5}\) - \(\frac{9}{20}\), в) \(\frac{23}{43}\) - \(\frac{11}{70}\), г) \(\frac{1}{8}\) + \(\frac{7}{12}\) - \(\frac{5}{9}\)

a) \(\frac{1}{3}\) + \(\frac{2}{5}\) = \(\frac{5}{15}\) + \(\frac{6}{15}\) = \(\frac{11}{15}\)
б) \(\frac{5}{5}\) - \(\frac{9}{20}\) = 1 - \(\frac{9}{20}\) = \(\frac{20}{20}\) - \(\frac{9}{20}\) = \(\frac{11}{20}\)
в) \(\frac{23}{43}\) - \(\frac{11}{70}\) = \(\frac{23 \cdot 70 - 11 \cdot 43}{43 \cdot 70}\) = \(\frac{1610 - 473}{3010}\) = \(\frac{1137}{3010}\)
г) \(\frac{1}{8}\) + \(\frac{7}{12}\) - \(\frac{5}{9}\) = \(\frac{9}{72}\) + \(\frac{42}{72}\) - \(\frac{40}{72}\) = \(\frac{51}{72}\) - \(\frac{40}{72}\) = \(\frac{11}{72}\)