find the perimeter of each of the following shapes take Pi is equal to 3.14
Answers
Answer:
Step-by-step explanation:
Figure 1
radius of both circles = 16 cm / 2
= 8 cm
Perimeter of the figure = Circumference of 2 semicircles + 2 Breadth of the rectangles
= 2 × 1 / 2 × 2 π r + 2 × 3 cm
= 2 π r + 6 cm
= 2 × 3.14 × 8 cm + 6 cm
= 50.24 cm + 6 cm
= 56.24 cm
Perimeter is 56.24 cm
Figure 2
Radius of big semi circle = 8 cm/2
= 4 cm
Radius of small semi - circle = 4 cm / 2
= 2 cm
Perimeter = 4 cm + 3 cm + 3 cm + circumference of the small semicircle + circumference of big semi circle.
= 10 cm + 1/2 × 2 π r + 1/2 × 2 π r
= 10 cm + 3.14 × r + 3.14 × r
= 10 cm + 3.14 × 4 + 3.14 × 2
= 10 cm + 12.56 + 6.28
= 28.84
The perimeter is 28.84 cm
Hope it helps ^__^
(a) Given, radius, r = 14 cm
We know that circumference
=
2
π
r
=
2
×
22
7
×
14
=
2
×
22
×
2
=
88
cm
(b) Given, radius, r = 28 mm,
We know that circumference
=
2
π
r
=
2
×
22
7
×
28
=
2
×
22
×
4
=
176
mm
(c) Given, radius, r = 21 cm
We know that circumference
=
2
π
r
=
2
×
22
7
×
21
=
2
×
22
×
3
=
132
cm