1. find the area of a semi circle of diameter 14cm
2.find the area of a circle of radius 1cm
3.find the areaof a circular lawn whose diameter is 10cm

Respuesta :

#1

  • d=14cm
  • r=14/2=7cm

[tex]\\ \sf\longmapsto Area=\pi r^2[/tex]

[tex]\\ \sf\longmapsto Area=3.14(7)^2[/tex]

[tex]\\ \sf\longmapsto Area\approx 154cm^2[/tex]

#2

  • r=1cm

[tex]\\ \sf\longmapsto Area=\pi r^2[/tex]

[tex]\\ \sf\longmapsto Area=3.14(1)^2[/tex]

[tex]\\ \sf\longmapsto Area=3.14cm^2[/tex]

#3

  • d=10cm
  • r=5cm

[tex]\\ \sf\longmapsto Area=3.14(5)^2[/tex]

[tex]\\ \sf\longmapsto Area=3.14(25)[/tex]

[tex]\\ \sf\longmapsto Area=78.5cm^2[/tex]

Answer:

1. Diameter of a semicircles =14cm

Radius or semicircle =7cm

*Area if circle =pi radius 2

=22/7 × 7×7cm 2

=154cm 2

But semicircle is half if a circle so,

Area of a semicircle =1/2 ×154cm2

=77cm2

2. Radius of the circle =1cm

Area of the circle=pi radius 2

=3.14×1×1

=3.14cm2

3.Diameter of a circular lawn=10m

Radius of the circular lawn =5m

Area of the circular lawn =pi radius2

=3.14×5m×5m

=78.5m2

Hope this helps:)