Помогите пожалуйста решить 2 уравнения: a) 2 1/14 - 1 1/9x = 1 5/21 b) 3 3/8 : (1/14 - 1...

▪а)
$2 \frac{1}{14} - 1 \frac{1}{9} x = 1 \frac{5}{21} \\ 2 \frac{1}{14} - 1 \frac{5}{21} = 1 \frac{1}{9} x \\ 1 \frac{1}{9} x = 1 \frac{3 - 5 \times 2}{42} = 1 \frac{3 - 10}{42} = 1 - \frac{7}{42} = 1 - \frac{1}{6} = \frac{5}{6} \\ 1 \frac{1}{9} x = \frac{5}{6} \\ x = \frac{5}{6} \div \frac{10}{9} = \frac{5 \times 9}{6 \times 10} = \frac{3}{2 \times 2} = \frac{3}{4} \\ x = \frac{3}{4} = 0.75$

▪б)

$3 \frac{3}{8} \div ( \frac{1}{14} - 1 \frac{3}{4} ) \div 5 \frac{2}{3} = \frac{27}{8} \div ( - 1 \frac{ 21 -2 }{28} ) \div \frac{17}{3} = \frac{27}{8} \div ( - 1 \frac{19}{28} ) \times \frac{3}{17} = \frac{27}{8} \times ( - \frac{28}{47} ) \times \frac{3}{17} = - \frac{27 \times 7 \times 3}{2 \times 47 \times 17} = - \frac{567}{1598}$