In this question we have to the find the cost of
levelling the semi-circular flower beds at 60 paise
per square meter given that a rectangular park is
100 m by 50 m. It is surrounded by semi-circular
flower beds all round.
This question is from r d sharma class 10 maths.
I found this question while doing mensuration of
class 10.
I need help in getting the solution.
Given,
Length of the park = 100 m and the breadth of the park = 50 m
The radius of the semi-circular flower beds = half of the corresponding side of the rectangular park
Radius of the bigger flower bed = 100/2 = 50 m
And the radius of the smaller flower bed = 50/2 = 25 m
Total area of the flower beds = 2[Area of bigger flower bed + Area of smaller flower bed]
= 2[½ π(50)2 + ½ π(25)2]
= π[(50)2 + (25)2]
= 3.14 x [2500 + 625]
= 9812.5 m2
Now, rate of levelling flower bed = 60 paise per m2
Therefore,
The total cost of levelling = 9812.5 x 60 = 588750 paise
= Rs 5887.50