1,485 : (0,513 + 0,477) = 1,485 : 0,99 = 148,5 : 99 = 1,5
1) $\snippet{name: op_column, sign: '+', x: '0,513', y: '0,477', z: '0,990'}$;
2) $\snippet{name: long_division, x: 148.5, y: 99}$.

$\frac{1 - \frac{1}{\frac{3}{4} + 1}}{3} = \frac{1 - \frac{1}{1\frac{3}{4}}}{3} = \frac{1 - 1 : \frac{7}{4}}{3} = \frac{1 - \frac{4}{7}}{3} = \frac{\frac{3}{7}}{3} = \frac{3}{7} * \frac{1}{3} = \frac{1}{7}$