Question

A 7 m road surrounds a circular garden whose area is 5544 m². Find the area of the road and the cost of tarring it at the rate of Rs.150 per sq m.  

Answer 1

Area of garden = 5544 m² 

Radius of cirOJlar garden=

π r² = 5544

r² = ${\displaystyle 5544\times \frac{7}{22}}$

r² = 1764

r = 42 m

Radius of cirOJlar garden = 42 m 

Radius of garden with surrounding road =R = 42 + 7 m = 49 m 

Area of garden with surrounding road = π R²

${\displaystyle =\frac{22}{7}\times 49\times 49}$

= 7546 m²

Area of garden with surrounding road = 7546 m² 

Area of road =Area of garden with surrounding road - area of garden 

= 7546 - 5544 m² 

= 2002 m² 

Area of road = 2002 m² 

Cost of tarring one sq m = Rs. 150 

Cost of tarring area of road = Rs.( 150 x 2002) = Rs 3,00,300 

Cost of tarring the road = Rs. 3,00,300