Question

Find the area of the following figures

Answer 1

Answer:

692.37 cm²and 259.65 m²

Step-by-step explanation:

Fig . 01

d + 0.5d + 0.5d = 42

d + d = 42

2d = 42

d = 42 / 2

d = 21 cm

The shaded portion consists of 4 semicircles of diameter 21 cm.

i.e it consists of 2 circles of diameter 21 cm

Radius = r = diameter / 2 = 21/2 = 10.5 cm

Area of the circle = π r² = 3.14 * (10.5)² = 3.14 * 110.25 = 346.19 cm²

Area of shaded portion = 2 * Area of Circle = 2 * 349.16 = 692.37 cm²

FIG. 02

The inner part consists of 2 semi circle of diameter 10.5 m

i.e it consists of 1  circle of diameter 10.5 m

Radius = r = d/2 = 10.5 / 2 = 5.25 m

Diameter of outer circle = 21 m

Radius of outer circle = R = 21 / 2 = 10.5 m

Area of shaded portion = area of outer circle - area of inner circle

= π R² - π r²

= π (R² - r²)

= π (10.5² - 5.25²)

= π (110.25 - 27.56)

= 3.14 * 82.69

= 259.65 m²