To calculate the total stain needed:
\[ \text{Total Stain Needed} = \frac{\text{Total Area}}{\text{Coverage per Gallon}} \]
Where:
Deck stain coverage refers to the area that a specific amount of stain can cover. It depends on factors such as the type of wood, the condition of the deck, and the application method[^1^][^2^].
Let's assume the following values:
Using the formula:
\[ \text{Total Area} = (20 \times 15) + (40 \times 3) + (5 \times 15) = 300 + 120 + 75 = 495 \text{ sq ft} \]
\[ \text{Total Stain Needed} = \frac{495}{200} \approx 2.48 \text{ gallons} \]
The total stain needed is approximately 2.48 gallons.