Question

a circular Garden has radius 56 metre a 7 metre Wide Road runs outside around it find the area of the road what will it cost to gravel the road at rupees 50 per square metre​

Answer 1

Answer:

Area of Road is 2616.95 $metre^{2}$.

Cost to gravel the road is 130847.50 rupees.

Step-by-step explanation:

Radius of the Garden is R = 56 metre

So, area of the Garden is $\pi R^{2}$ = $\pi 56^{2}$ $metre^{2}$

Radius of the (Garden+Road) is (R+7) = (56 + 7) metre = 63 metre

So, area of the (Garden+Road) is $\pi (R+7)^{2}$ = $\pi 63^{2}$ $metre^{2}$

Now, (Area of Road) = (Area of Garden+Road) - (Area of Garden)

So, area of Road is

( $\pi 63^{2}$ - $\pi 56^{2}$ ) $metre^{2}$ = 2616.95 $metre^{2}$

Cost to gravel the Road is rupees 50 per $metre^{2}$.

So the total cost to gravel the road is

(Area of the Road)*(Cost per $metre^{2}$) = (2616.95 * 50) rupees = 130847.50 rupees.

Answer 2

Cost to gravel the road = Rs 1309

Step-by-step explanation:

Area of road = π (R²-r²)

R = 56 + 7 = 63 m

r = 56 m

Area = $\frac{22}{7}$ ( 63² - 56² )

  =$\frac{22}{7}$ (63 + 56) (63-56)

  =$\frac{22}{7}$ *119*7

=22*119

=2618  m²

Cost to gravel the road = $\frac{1}{2}$ * 2618

= Rs 1309