Question

The diameter of a semi-
circular plot is 21cm. Then
perimeter of the plot is
a) 42cm
b) 52cm
c) 15cm
d) 54cm​

Answer 1

Answer:

Given radius of semi -circular plot is r=21 m

as we know that

Perimeter of semi circle with radius r is πr and area of semi circle is

4

πr

2

So perimeter of semi-circular plot is π(21)=

7

22

×21=66 m

Area of semi-circular plot is

4

π(21)

2

=

7×4

22×21×21

=346.5 m

2

Answer 2

Diameter = 21cm

So, radius = 21/2

Perimeter of the semi circular plot = 22/7 × 21/2 = 11 × 3 = 33cm.

Perimeter of the semi circular is 33cm.

Your options are not correct.