Вычислите! а)-7/18 - ( -4 5/12 + 4/9 ). б) 3/16* (-4/15) - 11/12 : 1 5/6

Решите задачу:

$- \frac{7}{18} - ( - 4 \frac{5}{12} + \frac{4}{9} ) = - \frac{7}{18} + 4 \frac{5}{12} - \frac{4}{9} = 4\frac{ - 14 + 15 - 16}{36} = 4 \frac{ - 15}{36} = 4 - \frac{5}{12} = 3 \frac{12 - 5}{12} = 3 \frac{7}{12} \\$

$\frac{3}{16} \times ( - \frac{4}{15} ) - \frac{11}{12} \div 1 \frac{5}{6} = - \frac{1}{4 \times 5} - \frac{11}{12} \div \frac{11}{6} = - \frac{1}{20} - \frac{11 \times 6}{12 \times 11} = - \frac{1}{20} - \frac{1}{2} = - \frac{1}{20} - \frac{10}{20} = - \frac{11}{20} = 0.55 \\$