he inner perimeter of a racetrack is 400 m and the outer perimeter is

1.	he inner perimeter of a racetrack is 400 m and the outer perimeter is 488 m. The lengthf each straight portion is 90 m. Find the cost of developing the track at the rate of12.50 per m
Answer» L = length of the straight portion = 90mRadius of the outer perimeter = RRadius of the inner perimeter = r outer perimeter = 2 L + 2π R = 488 m So R = 49 minner perimeter = 2 L + 2π r = 400 m so r = 35 m Area of the track (between inner perimeter and outer perimeter)= 2 * L * (R-r) +π (R² - r²)= 6, 216 m² Cost of development = 6, 216 * 12.50 = Rs 77,700.

he inner perimeter of a racetrack is 400 m and the outer perimeter is 488 m. The lengthf each straight portion is 90 m. Find the cost of developing the track at the rate of12.50 per m

Answer»

L = length of the straight portion = 90mRadius of the outer perimeter = RRadius of the inner perimeter = r

outer perimeter = 2 L + 2π R = 488 m So R = 49 minner perimeter = 2 L + 2π r = 400 m so r = 35 m

Area of the track (between inner perimeter and outer perimeter)= 2 * L * (R-r) +π (R² - r²)= 6, 216 m²

Cost of development = 6, 216 * 12.50 = Rs 77,700.