Question

Cost of circular Park rupees 5 per meter square is rupees 27720 at the path of uniform width runs around the park the cost of gravelling the path at the rate of rupees 3.50 per metre square is rupees 10780. Find the cost of fencing the path on both the sides at rate of rupees 2.10per metre square

Answer 1

5*π*r^2=27720
22/7*r^2=5544
r^2=252*7=1764
r=42
path=π*(R^2-r^2)
3.5*π*(R^2-r^2)=10780
11*(R^2-1764)=10780
R^2=980+1764
R=52.34
inner fencing =2πr*2.1=554.4
outer fencing=2πR*2.1=690.8
total=1244.2