This is a nice presentation from Jerry Howard. In this video, one can learn how to estimate the concrete slabs precisely.
As an example, a rectangular concrete pad is taken with 40 feet length, 12 feet width and 4” thickness.
To find out the volume of this concrete pad, apply the following formula :-
V = L x W x H = 40 x 12 x .334 (4” is converted to feet by dividing with 12) = 160.32 ft3
But, if you want to purchase concrete from any company, they sell it in cubic yards. So, you have to convert unit of measurement from cubic feet to cubic yards.
To do this, you have to apply the following trick :-
160.32 ft3/1 = 1 yd3/27 ft3 = 160.32/27 yd3 = 5.9 yd3 = 6 yards (approx) [as one cubic yard = 27 cubic feet)
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