Question

Diameter of a Circular garden is 42m. There is a 3.5m wide road around the garden. Find the area of the road.​

Answer 1

Step-by-step explanation:

Diameter Of Circle garden = 42 m (Given)

Radius Of circular garden = 42/2 ( Half diameter)

Radius of circular garden = 21 m

width if road = 3.5 m (Given)

Radius of outer circle = radius + widths of road

Widths of road = 21 + 3.5

Width of road = 24 . 5

Area Of Road = Area Of outer circle - Area of circular garden

Let Supposed R1 and r2

Area Of Road = πR^2 - πr^2

Area of road = π ( R^2 - r^2 ) ( Take pie common each side)

Area of road = 22/7 ( 24.5 ) ^2 - ( 21 ) ^2

Area of road = 22/7 (24.5+21) - ( 24.5 -21)

Using Identities

a^2 - b^2 = (a+b) ( a-b)

= 22/7 × 45.5 × 3.5

= 22 × 45.5 × 0.5

= 500 . 50 sq m

The Area Of Road 500 . 50 Sq m