To find the average amount of rain that fell in one year, you can divide the total rainfall by the number of years.
Given that it rained 464 inches in 2 years, the calculation is:
\[ \text{Average rainfall per year} = \frac{\text{Total rainfall}}{\text{Number of years}} = \frac{464 \text{ inches}}{2 \text{ years}} = 232 \text{ inches/year} \]
So, on average, 232 inches of rain fell in one year.