4 My roof covers 3000 square feet level I bought three 80gal

4. My roof covers 3000 square feet (level). I bought three 80-gallon rain barrels for my three downspouts to collect water for my garden irrigation. What is the total volume of my rain barrels? There was a 0.5 inch rainfall this afternoon. How many gallons of water bypassed my rain barrels? The rain barrels have covers, so assume no evaporational loss from the rain barrels.

Solution

since there are 3 rain barrels

the total volume of rain barrel is 3 * 80 = 240 gallons

For every inch of rain that falls on one square foot of your roof, one can collect just over half a gallon of rainwater that is 0.6 gallons.

the roof covers 3000 square feet

3000 square feet can collect 3000*.6 = 1800 gallons for 1 inch rain even

therefore, for .5 inch it can collect 1800/ 2 = 900 gallons of water