पंधरा भागिले 15 भागिले चार चार भागिले 15 20 भागिले 50 50 / 4 15 / 20 / 4

$$\frac{15}{15} = 1$$

The result is $\boxed{1}$.

$$\frac{15}{4} = 3.75$$

The result is $\boxed{3.75}$.

$$\frac{4}{15} \approx 0.2667$$

The result is $\boxed{\frac{4}{15} \text{ or } 0.2667}$.

$$\frac{20}{50} = \frac{2}{5} = 0.4$$

The result is $\boxed{0.4}$.

$$\frac{50}{4} = \frac{25}{2} = 12.5$$

The result is $\boxed{12.5}$.

First, divide 15 by 20:

$$\frac{15}{20} = \frac{3}{4} = 0.75$$

Next, divide the result by 4:

$$\frac{0.75}{4} = 0.1875$$

Alternatively, as a fraction:

$$\frac{15}{20} \div 4 = \frac{15}{20 \times 4} = \frac{15}{80} = \frac{3}{16}$$

The result is $\boxed{0.1875 \text{ or } \frac{3}{16}}$.