The given question asks to convert the fraction $\frac{4}{9}$ into its decimal form, and if necessary, use a bar to indicate repeating digits.

Let's perform the division of 4 by 9:

$4 \div 9 = 0.4444\ldots$

The digit 4 repeats indefinitely, so the decimal representation of $\frac{4}{9}$ is:

$0.\overline{4}$

The bar (overline) is placed over the repeating digit 4 to indicate that it repeats infinitely.

Would you like further details or have any questions?

Here are 5 related questions to expand your understanding:

1. How can you convert any fraction to a decimal?
2. What is a repeating decimal, and how do you represent it?
3. How can you identify if a decimal is terminating or repeating?
4. What are some examples of fractions with non-repeating decimals?
5. Can repeating decimals always be written as fractions?

Tip: You can always determine if a fraction results in a repeating decimal by checking the denominator—if it has factors other than 2 and 5, the decimal will repeat.