(C x W x 0.052) / HR = Sprinkler time (in minutes)
C = coverage area (area in square feet covered by your sprinkler setting)
W = water depth (the desired water depth in inches)
0.052 = .052 (it takes 52 gallons of water per 1,000 sq feet to soak an area 1 inch deep)
HR = hose rate (gallons per minute coming out of your hose)
= sprinkler time (how long you should run your sprinkler in minutes)
Sample calculation:
5,000 (Coverage area) x 1 (water depth) x .052 / 1 (hose rate) = 260 minutes or 4.33 hours