It is 1.25cft

Portland cement weighs 1506kg/m^3 Dry sand weighs 1602kg/m^3 1/5 of the mixture is cement so multiply 1506 by .2 to find total weight and divide by 50 to find number of bags

A mixer will produce 1.25 cubic feet of cement. How many bags of concrete will produce 1,25 cubic feet