To find out what percent of his goal Leon reached, you can use the formula:
\[ \text{Percent of goal reached} = \left( \frac{\text{Amount saved}}{\text{Goal}} \right) \times 100 \]
In this case, Leon saved $120 and his goal was $100.
So,
\[ \text{Percent of goal reached} = \left( \frac{120}{100} \right) \times 100 \]
Calculating that:
\[ \text{Percent of goal reached} = 1.2 \times 100 = 120% \]
Therefore, Leon reached 120% of his goal.