Advertisements
Advertisements
Question
There is a path of uniform width 7 m round and outside a circular garden of diameter 210 m. Find the area of the path.
Advertisements
Solution

Diameter = 210 m
Radius of inner circle r2 = 105 m
Width = 7m
Radius of outer circle r1 = 105 + 7 = 112 m
∴ Area of path = `pir_1^2 - pir_2^2`
= `pi[r_1^2 - r_2^2]`
= `22/7(r_1 + r_2)(r_1 + r_2)`
= `22/7 (112 + 105)(112 - 105)`
= `22/7 xx 217 xx 7`
= 4774 m2
APPEARS IN
RELATED QUESTIONS
A room is 16 m long and 13.5 m broad. Find the cost of covering its floor with 75-cm-wide carpet at ₹ 60 per metre.
A footpath of uniform width runs all around the inside of a rectangular field 54 m long and 35 m wide. If the area of the path is 420 m2, find the width of the path.
In the the following figure, PSR, RTQ and PAQ are three semicircles of diameter 10 cm, 3 cm and 7 cm respectively. Find the perimeter of shaded region.

A circular park has a path of uniform width around it. The difference between the outer and inner circumferences of the circular path is 132 m. Its width is
Find the lengths of the arcs cut off from a circle of radius 12 cm by a chord 12 cm long. Also, find the area of the minor segment. [Take π = 3.14 and `sqrt(3) = 1.73`.]
If a square is inscribed in a circle, find the ratio of the areas of the circle and the square.
On a circular table cover of radius 42 cm, a design is formed by a girl leaving an equilateral triangle ABC in the middle, as shown in the figure. Find the covered area of the design. `["Use" sqrt(3) = 1.73 and π = 22/7.]`

In the given figure, ∆ABC is right-angled at A. Semicircles are drawn on AB, AC and BC as diameters. It is given that AB = 3 cm and AC = 4 cm. Find the area of the shaded region.

The radii of the inner and outer circumferences of a circular running track are 63 m and 70 m respectively. Find :
(i) the area of the track ;
(ii) the difference between the lengths of the two circumferences of the track.
Perimeter of a sector of a circle whose central angle is 90° and radius 7 cm is ______.
