A proportion typically compares two ratios that are set equal to each other. Since you provided only one ratio, $\frac{6}{8}$, we need more information to find the missing number.

If you want to complete the proportion, it could be something like:

$\frac{6}{8} = \frac{x}{y}$

where $x$ or $y$ is the missing number. Could you clarify which variable (the numerator or denominator) is missing and if there's another ratio to compare it to? Alternatively, if you're asking to simplify the fraction, $\frac{6}{8}$ simplifies to $\frac{3}{4}$.

Let me know what more you need, and I'll provide further details!

Do you have any specific questions related to this proportion? Here are some that might help:

1. Would you like to simplify the ratio?
2. Are you trying to find the missing number in a proportion equation?
3. Is there a specific context where you're using this proportion?
4. Do you need to find a cross-multiplication solution?
5. Are there any constraints or additional conditions?

Tip: When dealing with proportions, cross-multiplying is often a helpful strategy to solve for a missing variable.