Question

вычислите пожалуйста 3 1/4:(3/4-7/5)-2* 1 3/7

Answer 1

$3 \frac{1}{4} \div ( \frac{3}{4} - \frac{7}{5} ) - 2 \times 1 \frac{3}{7} = \\ \frac{13}{4} \div ( \frac{15}{20} - \frac{28}{20} ) - \frac{2}{1} \times \frac{10}{7} = \\ \frac{13}{4} \div ( - \frac{13}{20} ) - \frac{20}{7} = \\ - ( \frac{13}{4} \times \frac{20}{13} ) - \frac{20}{7} = \\ - \frac{5}{1} - \frac{20}{7} = - \frac{35}{7} - \frac{20}{7} = - \frac{55}{7} = \\ = - 7 \frac{6}{7}$