Вычислите значение выражения наиболее удобным способом:
1) $4\frac{4}{9} * \frac{5}{8} + \frac{5}{8} * 3\frac{5}{9}$;
2) $3\frac{7}{8} * \frac{4}{5} - 1\frac{5}{8} * \frac{4}{5}$;
3) $2\frac{11}{15} * 1\frac{1}{19} - 1\frac{1}{19} * \frac{3}{10} - 1\frac{1}{6} * 1\frac{1}{19}$;
4) $4\frac{7}{9} * 1\frac{13}{14} - 3\frac{7}{12} * 1\frac{13}{14} + 1\frac{13}{14} * 1\frac{13}{18}$.
$4\frac{4}{9} * \frac{5}{8} + \frac{5}{8} * 3\frac{5}{9} = \frac{5}{8} * (4\frac{4}{9} + 3\frac{5}{9}) = \frac{5}{8} * 8 = 5$
$3\frac{7}{8} * \frac{4}{5} - 1\frac{5}{8} * \frac{4}{5} = (3\frac{7}{8} - 1\frac{5}{8}) * \frac{4}{5} = 2\frac{1}{4} * \frac{4}{5} = \frac{9}{4} * \frac{4}{5} = \frac{9}{5} = 1\frac{4}{5}$
$2\frac{11}{15} * 1\frac{1}{19} - 1\frac{1}{19} * \frac{3}{10} - 1\frac{1}{6} * 1\frac{1}{19} = (2\frac{11}{15} - \frac{3}{10} - 1\frac{1}{6}) * \frac{20}{19} = (2\frac{22}{30} - \frac{9}{30} - 1\frac{5}{30}) * \frac{20}{19} = \frac{19}{15} * \frac{20}{19} = \frac{1}{15} * \frac{20}{1} = \frac{4}{3} = 1\frac{1}{3}$
$4\frac{7}{9} * 1\frac{13}{14} - 3\frac{7}{12} * 1\frac{13}{14} + 1\frac{13}{14} * 1\frac{13}{18} = (4\frac{28}{36} - 3\frac{21}{36} + 1\frac{26}{36}) * 1\frac{13}{14} = 2\frac{11}{12} * 1\frac{13}{14} = \frac{35}{12} * \frac{27}{14} = \frac{5}{4} * \frac{9}{2} = \frac{45}{8} = 5\frac{5}{8}$
Пожауйста, оцените решение
