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

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#### Solution

Diameter of the garden(d) = 42 m

Radius, r = 21 m

Diameter of the garden including the road = 42 + 3.5 + 3.5 = 49 m

Radius of the garden with the road = 24.5 m

Area of road =

Ar of garden with road - Ar of garden

= πR² = πr²

= π (R² - r² )

= `22/7 ( (24.5)² - 21² )`

= `22/7 xx (600.25 - 441)`

= `22/7 xx 159.25`

= 500.5 m²

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