To convert the fraction $\frac{20}{10000}$ to a decimal, divide 20 by 10000:

$\frac{20}{10000} = 0.002$

So, $20/10000$ as a decimal is $0.002$.

Would you like more details or have any questions? Here are some related questions:

1. How do you convert fractions to decimals?
2. What are some examples of converting other fractions to decimals?
3. What is the significance of decimal places in different contexts?
4. How can you simplify fractions before converting them?
5. What is the relationship between percentages and decimals?

Tip: When converting a fraction to a decimal, you can also multiply the numerator and denominator by the same number to make the division simpler.