Question

The radius of the field in the form of sector is 21 m. The cost of constructing a wall around the field is rupees 1875 at the rate of rupees 25 per meter. If it costs rupees 10 per m² to till the field, what will be the cost of tilling the whole field?

Answer 1

The cost is rs 3465.
The explanation is in the image.

Hope This Helps :)

Answer 2

Answer:

Cost of tilling= Rs 69.3

Step-by-step explanation:

Radius of the field =  21 m

Perimeter of the sector = Cost of constructing wall / Rate per meter

= 1875 /25 = 75 m

2 * r + l = 75 m

2 *  21 + l = 75 m

42 + l = 75

l = 75 - 42 = 33

theta = l/r = 33/21 = 11/7 radian = 11/7* 180 * 7/22 = 180/2 = 90 degree

Area of the field = theta/360* πr² = 90/360 πr² = 1/4 * 22/7 * 21 * 21

1/4 * 3 * 22 * 21

= 1386/4 m²

Cost of tilling = Area of the field * Cost per m²

= 1386/4 *  10 = 693/10 = Rs 69.3