Formula to find the perimeter of a semicircular region:
if radius given: [tex]P=2r[/tex] + [tex]\pi r[/tex] {r = radius}
if diameter given: [tex]P=d+\pi r[/tex] {d = diameter}
Take [tex]\pi[/tex] as 3.14
Q4.
Diameter = 28 yd
Radius = 28/2 = 14 yd
[tex]P=28+\pi (14)[/tex]
[tex]P=28+(3.14)(14)[/tex]
[tex]P=28+14.96[/tex]
[tex]P=42.96[/tex] yd
Q5.
Radius = 7.5 ft
Diameter = 7.5 × 2 = 15 ft
[tex]P=2(7.5)+\pi (7.5)[/tex]
[tex]P=2(7.5)+(3.14)(7.5)[/tex]
[tex]P=15+23.55[/tex]
[tex]P=38.55[/tex] ft
Q6.
Diameter = 11 cm
Radius = 11/2 = 5.5 cm
[tex]P=11+\pi (5.5)[/tex]
[tex]P=11+(3.14)(5.5)[/tex]
[tex]P=11+17.27[/tex]
[tex]P=17.27[/tex] cm
I hope this helps...
Have a great day ahead :)
