Advertisements
Advertisements
Question
The cost of fencing a circular field at the rate of ₹ 240 per meter is ₹ 52,800. The field is to be ploughed at the rate of ₹ 12.50 per m2. Find the cost of pouching the field.
Advertisements
Solution
Let the radius of the field is r meter.
Therefore circumference of the field will be 2πr meter.
Now the cost of fencing the circular field is 52,800 at rate 240 per meter.
Therefore,
2πr. 240 = 52800
r = `[ 52800 xx 7 ]/[ 2 xx 240 xx 22 ]`
r = 35
Thus the radius of the field is 35 meter.
Now the area of the field will be :
πr2 = `( 22/7 )`.352 = 3850 m2
Thus the cost of ploughing the field will be:
3850 x 12.5 = 48,125 rupees.
APPEARS IN
RELATED QUESTIONS
The circumferences of two circles are in the ratio 2: 3. What is the ratio between their areas?
Two circular pieces of equal radii and maximum area, touching each other are cut out from a rectangular cardboard of dimensions 14 cm ⨯ 7 cm. Find the area of the remaining cardboard.
A wire when bent in the form of an equilateral triangle encloses an area of `121sqrt(3) "cm"^2`. The same wire is bent to form a circle. Find the area enclosed by the circle.
In a circle of radius 21 cm, an arc subtends an angle of 60° at the centre. The length of the arc is
The area of the circle is given below; find the diameter.
176 sq cm
A conical tent with a capacity of 600 m3 stands on a circular base of area 160 m2 Find in m2 the area of the canvas.
Complete the table below.
| Radius (r) | Diameter (d) | Circumference (c) |
| ...... | ...... | 616 cm |
Find the area and perimeter of the circles with following: Diameter = 77cm
The wheel of a car makes 10 revolutions per second. If its diameter is 70cm, find the speed of the car in km per hr.
A wire in the form of a circle of radius 42cm. It is bent into a square. Determine the side of the square and compare the area of the regions enclosed in the two cases.
