9/56-(7/15-5/12)*(3/14+1/2)

Решите задачу:

$\frac{9}{56} - ( \frac{7}{15} - \frac{5}{12} ) \times ( \frac{3}{14} + \frac{1}{2} ) = \frac{9}{56} - \frac{1}{20} \times \frac{5}{7} = \frac{9}{56} - \frac{1}{28} = \frac{1}{8} \\ 1) \: \frac{7}{15} - \frac{5}{12} = \frac{7 \times 4 - 5 \times 5}{60} = \frac{28 - 25}{60} = \frac{3}{60} = \frac{1}{20} \\ 2) \frac{3}{14 } + \frac{1}{2} = \frac{3 + 7}{14} = \frac{10}{14} = \frac{5}{7} \\ 3) \: \frac{1}{20} \times \frac{5}{7} = \frac{5}{20 \times 7} = \frac{1}{4 \times 7} = \frac{1}{28} \\ 4) \: \frac{9}{56} - \frac{1}{28} = \frac{9 - 2}{56} = \frac{7}{56} = \frac{1}{8}$