The 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.

Given that the diameter of the garden (inner circle) = 42m

Therefore, inner radius, r = 21m

Also, given that road surrounds the garden and is 3.5 m wide.

Therefore, the diameter of the road (outer circle) will be = 42+2(3.5) = 49m

And then outer radius, R = 24.5m

Now, the area of road = area of the outer circle – area of the inner circle

area of outer circle = πR²

= π(24.5)²

= 1885 sq m

area of inner circle = πr²

= π(21)²

= 1385 sq m

Hence, area of road = 1885-1385 = 500 sq m