Вычислим:
- $$4 - 1 \frac{9}{10} = 3 \frac{10}{10} - 1 \frac{9}{10} = 2 \frac{1}{10} = \frac{21}{10}$$
- $$\frac{3}{25} : \frac{21}{10} = \frac{3}{25} \times \frac{10}{21} = \frac{3 \times 10}{25 \times 21} = \frac{30}{525} = \frac{2}{35}$$
- $$\frac{10}{1} + \frac{2}{35} = \frac{10 \times 35}{35} + \frac{2}{35} = \frac{350}{35} + \frac{2}{35} = \frac{352}{35}$$
- $$\frac{352}{35} + \frac{4}{7} = \frac{352}{35} + \frac{4 \times 5}{7 \times 5} = \frac{352}{35} + \frac{20}{35} = \frac{372}{35} = 10 \frac{22}{35}$$
Ответ: $$10 \frac{22}{35}$$