Advertisements
Advertisements
प्रश्न
There are two circular gardens A and B. The circumference of garden A is 1.760 km and the area of garden B is 25 times the area of garden A. Find the circumference of garden B.
Advertisements
उत्तर
Let r be the radius of the circular garden A
Since the circumference of the garden A is 1.760 km = 1760 m, we have,
2πr = 1760 m
⇒ r = `[ 1760 xx 7 ]/[ 2 xx 22 ]` = 280 m
Area of garden A = πr2 = `22/7` x 2802 m2
Let R be the radius of the circular garden B.
Since the area of the garden, B is 25 times the area of garden A, We have,
πR2 = 25 x πr2
⇒ πR2 = 25 x π x 2802
⇒ R2 = 1960000
⇒ R = 1400 m
Thus circumference of garden B = 2πR
= `2 xx 22/7 xx 1400` = 8800 m = 8.8 km.
APPEARS IN
संबंधित प्रश्न
In PSR, RTQ and PAQ are three semicircles of diameters 10 cm, 3 cm and 7 cm respectively. Find the perimeter of the shaded region. [Use π=3.14]
A chord of a circle of radius 30 cm makes an angle of 60° at the centre of the circle. Find the areas of the minor major segments.
In the given figure, OPQR is a rhombus, three of whose vertices lie on a circle with centre O. If the area of the rhombus is `32sqrt(3)`, find the radius of the circle.
In the given figure, from a rectangular region ABCD with AB = 20 cm, a right triangle AED with AE = 9 cm and DE = 12 cm, is cut off. On the other end, taking BC as diameter, a semicircle is added on outside' the region. Find the area of the shaded region. [Use π = 3.14]
The radius of a circular garden is 100 m. There is a road 10 m wide, running all around it. Find the area of the road and the cost of levelling it at Rs 20 per m2. [Use π = 3.14]
The radii of two concentric circles are 19 cm and 16 cm respectively. The area of the ring enclosed by these circles is
The inner circumference of a circular track is 264 m and the width of the track is 7 m. Find:
(i) the radius of the inner track.
(ii) the radius of the outer circumference.
(iii) the length of the outer circumference.
(iv) the cost of fencing the outer circumference at the rate of ₹50 per m.
Sudhanshu divides a circular disc of radius 7 cm in two equal parts. What is the perimeter of each semicircular shape disc? (Use π = `22/7`)
In a circle of diameter 42 cm, if an arc subtends an angle of 60° at the centre, where `pi = 22/7` then length of an arc is ____________.
Is it true that the distance travelled by a circular wheel of diameter d cm in one revolution is 2 π d cm? Why?
