V_{wet} = Length \times Width \times Depth
V_{wet} = \pi \times (\frac{Diameter}{2})^2 \times Height
V_{dry} = V_{wet} \times 1.54
R = 1 + S + A
Mass_{cement} = (\frac{1}{R} \times V_{dry}) \times Density_{cement}
Mass_{sand} = (\frac{S}{R} \times V_{dry}) \times Density_{sand}
For a Slab / Footing: $V_{wet} = Length \times Width \times Depth$ For a Column / Post: $V_{wet} = \pi \times (\frac{Diameter}{2})^2 \times Height$
$V_{dry} = V_{wet} \times 1.54$
Sum of Ratios (R): $R = 1 + S + A$ Mass of Cement: $Mass_{cement} = (\frac{1}{R} \times V_{dry}) \times Density_{cement}$ Mass of Sand: $Mass_{sand} = (\frac{S}{R} \times V_{dry}) \times Density_{sand}$ Mass of Stone: $Mass_{stone} = (\frac{A}{R} \times V_{dry}) \times Density_{stone}$
$Total\ Bags = \frac{Total\ V_{wet}\ (in\ ft^3)}{Yield\ per\ Bag\ (in\ ft^3)}$ (e.g., An 80 lb bag yields approximately 0.60 ft³ of concrete)