Diameter of semicircle is equal to 2 km.
Given: Perimeter of semicircle = P = 5.14 km
d=?
Perimeter of semicircle is given by
[tex]P = (\pi \times r ) + d\\5.14 = (\pi \times r ) + d\\\\Since \ d=2r; \ r=\frac{d}{2} \\5.14 = (\pi \times \frac{d}{2}) + d\\[/tex]
Simplifying the above equation
[tex]5.14 = ( \frac{(\pi \times d) + 2d}{2}) \\\\5.14 \times 2 = d(\pi +2)\\\\d=\frac{5.14 \times 2}{\pi +2 }\\[/tex]
As value of pi = 3.14, equation becomes
[tex]d=\frac{5.14 \times 2}{\ 3.14 +2} = \frac{10.28}{5.14} =2 \ km[/tex]
Diameter of semicircle is equal to 2 km.
