Question

срочно
1.4/5+3/7
2.5/12+9/20
3.5/18+4/45​

Answer 1

Ответ:

Пошаговое объяснение:

$\frac{4}{5} + \frac{3}{7} = \frac{4*7}{35} + \frac{3*5}{35} = \frac{28}{35} + \frac{15}{35} = \frac{43}{35} = 1 \frac{8}{35} \\ \\ \frac{5}{12} + \frac{9}{20} = \frac{5*5}{60} + \frac{9*3}{60} = \frac{25}{60} + \frac{27}{60} = \frac{52}{60} = \frac{13}{15} \\ \\ \frac{5}{18} + \frac{4}{45} = \frac{5*5}{90} + \frac{4*2}{90} = \frac{25}{90} + \frac{8}{90} = \frac{33}{90} = \frac{11}{30}$