The notation "0.3̅" represents a repeating decimal, specifically the number 0.3333..., where the digit 3 repeats indefinitely. This means that no matter how far you go in the decimal, there will always be another 3 following it. In mathematical terms, it is equivalent to the fraction 1/3. Repeating decimals like "0.3̅" can be converted into fractions. For example, if you let x equal 0.3̅, multiplying both sides by 10 gives you 10x = 3. By subtracting the original x from this equation, you can solve for x, confirming that 0.3̅ equals 1/3.