Advertisements
Advertisements
प्रश्न
In the following figure, a rectangle ABCD enclosed three circles. If BC = 14 cm, find the area of the shaded portion (Take π = 22/7)

Advertisements
उत्तर
AB = 14 + 14 + 14 + 7
= 49 cm
BC = 14 cm
AB = 49 cm
Area of ABCD = 49 × 14 cm2
Diameter of circle = 14 cm
Radius = `"Diameter"/2 = 7 cm`
Area of the circle = πr2
Area of the circle = `22/7xx7^2`
= `22/7xx49`
= `1078/7`
= 154 cm2
Area of 3 circles = 3 × 154 cm2
= 462 cm2
Area of the semicircle = `1/2` πr2
= `1/2xx22/7xx7^2`
= `22/14xx49`
= `1078/14`
= 77 cm2
⇒ Area of shaded portion = 686 – (462 + 77) cm2
= 686 – 539 cm2
= 147 cm2
Hence, the area of the shaded portion is 147 cm2.
APPEARS IN
संबंधित प्रश्न
A rectangular plot measure 125 m by 78 m. It has gravel path 3 m wide all around on the outside. Find the area of the path and the cost of gravelling it at` ₹ 75 per m^2`
The cost of painting the four walls of a room 12 m long at `₹ 30 per m^2 is ₹ 7560 per m^2` and the cost of covering the floor with the mat at ₹` 25 per m^2 is ₹ 2700 `. find the dimensions of the room.
A square water tank has its side equal to 40 m. There are four semi-circular grassy plots all round it. Find the cost of turfing the plot at Rs. 1.25 per square metre (Take π = 3.14).
If a square is inscribed in a circle, what is the ratio of the areas of the circle and the square?
The area of the circle that can be inscribed in a square of side 10 cm is
Find the area of the shaded portion in each of the following diagrams:
(i)

(ii)

Find the length of the rope by which a bull must be tethered in order that it may be able to graze an area of 2464 m2
The formula used to find the area of the circle is ________ sq.units
If the perimeter of a semicircular protractor is 72 cm where `pi = 22/7`, then the diameter of protractor is ____________.
A table cover of dimensions 3 m 25 cm × 2 m 30 cm is spread on a table. If 30 cm of the table cover is hanging all around the table, find the area of the table cover which is hanging outside the top of the table. Also find the cost of polishing the table top at ₹ 16 per square metre.
