A town's public works department has ordered sand to spread on roadways during the upcoming winter snows. The delivered sand forms a right cone 36 feet high and a base diameter of 54 feet. How many cubic yards of sand has the department received?
A cone is 1/3 of a cylinder the formula is V = (1/3) pi * r^2 * h so we have V = (1/3) * pi * 27^2 * 36 = 27482.65253 cubic feet
However, 27 cubic feet = 1 cubic yard so 27482.65253/27 = 1017.87602 cubic yards
oh thanks can you help me with quite a few more please
A contractor has installed a silt fence around an area that is semi-circular and level to prevent soil from the construction site entering nearby streams. The diameter of the semi-circle is 1200 feet. How many linear feet of fence does the contractor need to use to enclose the area?
Does the fence connect the two ends of the semicircles?
semicircle*
Anyways, you'd find the circumference of a circle (2*pi*r). Semi-circle is half of a circle so you can use (pi*r). The radius is 600 ft, so for the semi-circular part of the fence you'd need approximately 1884.96 linear ft of fence. If you connect the two ends of the semi-circle, add another 1200 linear feet so you'd have 3084.96 linear ft.
oh ok thanks
how many acres would be enclosed by the fence?
You find the area of the semicircle then. (pi * r^2)/2. Then convert to acres. 1 acre = 43,560ft^2
oh wow thanks once again. i have about 3 more questions, do you have the time?
Just post them, I'm sure someone will answer.
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