Question

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?

Answer 1

Answer:

The answer is $(600\pi+1,200)\ ft$ or $3,085\ ft$

Step-by-step explanation:

we know that

The circumference of a circle is equal to

$C=\pi D$

where

D is the diameter of the circle

In this problem, to calculate how many linear feet are needed, find the perimeter of a semicircle

so

$\frac{\pi D}{2}+D$

we have

$D=1,200\ ft$

substitute the value

$\frac{\pi (1,200)}{2}+1,200=(600\pi+1,200)\ ft$

$(600\pi+1,200)\ ft=3,085\ ft$

Answer 2

3085 
[(1200xpí)/2]+1200