Answer
101,743 bags
Work Step by Step
First, we need to convert the measurements of the plot to the same units as the depth of the topsoil. We know that the plot measures 200 m by 300 m, so we can calculate the area of the plot as:
Area of the plot = 200 m * 300 m = 60000 m^2
We also need to convert the depth of the topsoil to the same units as the area of the plot. We know that the depth of the topsoil is 4.0 cm, so we can convert it to meters by dividing by 100:
Depth of the topsoil = 4.0 cm / 100 = 0.04 m
We know that one 40-lb bag of topsoil will cover 10 sq ft to a depth of 1.0 inch, so we can calculate the volume of topsoil in one bag as:
Volume of topsoil in one bag = 10 sq ft * 1.0 inch = 10*0.0833 ft^3 = 0.833 ft^3
Now we can calculate the number of bags needed to cover the plot:
Number of bags = (Area of the plot * Depth of the topsoil) / Volume of topsoil in one bag
Number of bags = (60000 m^2 * 0.04 m) / 0.833 ft^3
Number of bags = (60000 * 0.04 * 3.2808^3) / 0.833
Number of bags =101,743.22 or about 101,743 bags of topsoil.
So, you would need about 101,743 bags of topsoil to cover the plot to a depth of 4 cm.
