Converting Fractions to Decimals divide the numerator by the denominator and round if needed

$$2 \div 5 = 0.4$$

The decimal form is $\boxed{\text{0.4}}$.

2) $\frac{9}{25}$

$$9 \div 25 = 0.36$$

The decimal form is $\boxed{\text{0.36}}$.

3) $\frac{3}{16}$

$$3 \div 16 = 0.1875$$

The decimal form is $\boxed{\text{0.1875}}$.

4) $\frac{1}{3}$

The decimal form is approximately $\boxed{\text{0.333}}$.

5) $\frac{17}{11}$

The decimal form is approximately $\boxed{\text{1.545}}$.

6) $\frac{17}{20}$

$$17 \div 20 = 0.85$$

The decimal form is $\boxed{\text{0.85}}$.