To find out how much water David would evenly distribute for each square foot of his garden, you can divide the total gallons of water (425 gallons) by the total area of the garden (36 square feet).
The calculation is as follows:
\[ \text{Water per square foot} = \frac{\text{Total gallons}}{\text{Total square feet}} = \frac{425 \text{ gallons}}{36 \text{ square feet}} \]
Now, performing the division:
\[ \frac{425}{36} \approx 11.8 \]
So, rounded to the nearest tenth, David would distribute approximately 11.8 gallons per square foot.