Question

помогите пожалуйста​

Answer 1

А)

$1 \frac{4}{5} - \frac{9}{10} = 1 \frac{4 \times 2}{5 \times 2} - \frac{9}{10} = 1 \frac{8}{10} - \frac{9}{10} = \frac{10 + 8}{10} - \frac{9}{10} = \frac{18}{10} - \frac{9}{10} = \frac{9}{10}$

Б)

$\frac{7}{24} + \frac{5}{24} = \frac{12}{24} = \frac{12 \div 12}{24 \div 12} = \frac{1}{2}$

В)

$\frac{17}{18} - \frac{5}{18} = \frac{12}{18} = \frac{12 \div 6}{18 \div 6} = \frac{2}{3}$