ГДЗ по математике 5 класс Мерзляк ФГОС Задание 1072

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\[1)\ 3\frac{5}{14} \cdot \frac{7}{9} - 2\frac{3}{14} \cdot \frac{7}{9} =\]

\[= \frac{7}{9} \cdot \left( 3\frac{5}{14} - 2\frac{3}{14} \right) = \frac{7}{9} \cdot 1\frac{2}{14} =\]

\[2)\ 7\frac{1}{5} \cdot 2\frac{1}{8} + 7\frac{1}{5} \cdot 1\frac{5}{8} =\]

\[= 7\frac{1}{5} \cdot \left( 2\frac{1}{8} + 1\frac{5}{8} \right) = \frac{36}{5} \cdot 3\frac{6}{8} =\]

\[= \frac{36}{5} \cdot 3\frac{3}{4} =\]

\[3)\frac{3}{4} \cdot 1\frac{3}{5} + 1\frac{3}{5} \cdot 1\frac{3}{8} - 1\frac{1}{2} \cdot 1\frac{3}{5} =\]

\[= 1\frac{3}{5} \cdot \left( \frac{3}{4} + 1\frac{3}{8} - 1\frac{1}{2} \right) =\]

\[= \frac{8}{5} \cdot \left( \frac{3^{\backslash 2}}{4} + \frac{11}{8} - \frac{3^{\backslash 4}}{2} \right) =\]

\[= \frac{8}{5} \cdot \frac{6 + 11 - 12}{8} = \frac{8}{5} \cdot \frac{5}{8} = 1\]

\[= 1\frac{13}{14} \cdot \left( 4\frac{7^{\backslash 4}}{9} - 3\frac{7^{\backslash 3}}{12} + 1\frac{13^{\backslash 2}}{18} \right) =\]

\[= \frac{27}{14} \cdot \left( 4\frac{28}{36} - 3\frac{21}{36} + 1\frac{26}{36} \right) =\]

\[= \frac{27}{14} \cdot 2\frac{33}{36} = \frac{27}{14} \cdot 2\frac{11}{12} =\]

\[= \frac{27}{14} \cdot \frac{35}{12} =\]