To find the percentage of Leah's action figure collection that she keeps on her wall, we can use the formula for percentage:
\[ \text{Percentage} = \left(\frac{\text{Part}}{\text{Whole}}\right) \times 100 \]
In this case, the "Part" is the number of action figures she keeps on her wall (430), and the "Whole" is the total number of action figures in her collection (500).
Substituting the values into the formula:
\[ \text{Percentage} = \left(\frac{430}{500}\right) \times 100 \]
Calculating the fraction:
\[ \frac{430}{500} = 0.86 \]
Now, convert the fraction to a percentage:
\[ 0.86 \times 100 = 86 \]
Therefore, Leah keeps 86% of her action figure collection on her wall.