Question

математика помогите пж​

Answer 1

$(\frac{3}{4} - \frac{4}{5}) + 7.8 - ( \frac{2}{3} + \frac{4}{7} ) \times ( - \frac{7}{13} ) = - \frac{1}{20} \times \frac{39}{5} - \frac{26}{21} \times ( - \frac{7}{13} ) = - \frac{39}{100} + \frac{2}{3} = \frac{83}{300}$