Advertisements
Advertisements
Question
Find the area of the shaded portion in each of the following diagrams:
(i)

(ii)

Advertisements
Solution
(i)

Radius of circle, r = 7 cm
∴ Side of square = 7 + 7 = 14 cm
Area of circle = `pir^2`
= `22/7 xx 7xx 7`
= 154 cm2
Area of square = `14 xx 14`
= 196 cm2
∴ Area of shaded portion = 196 - 154
= 42 cm2
(ii)
Radii of concentric circles are
`r_1 = 4.5`m
`r_2 = 2.5`m

∴ Area of shaded portion = `pir_1^2 - pir_2^2`
= `pi[r_1^2 - r_2^2] = 22/7[(4.5)^2 - (2.5)^2]`
= `22/7 xx (4.5 + 2.5) (4.5 - 2.5)`
= `22/7 xx 14 = 44` cm2
APPEARS IN
RELATED QUESTIONS
In the following figure, OABC is a square of side 7 cm. If OAPC is a quadrant of a circle with centre O, then find the area of the shaded region. (Use π = 22/7)

If diameter of a circle is increased by 40%, then its area increase by
The perimeter of a certain sector of a circle of radius 6.5 cm is 31 cm. Find the area of the sector.
Find the area of the shaded region in the given figure, if ABCD is a rectangle with sides 8 cm and 6 cm and O is the centre of the circle.

The short and long hands of a clock are 4 cm and 6 cm long respectively. Find the sum of distances travelled by their tips in 2 days.
A circle of the largest area is cut from a rectangular piece of cardboard with dimensions 55 cm and 42 cm. Find the ratio between the area of the circle cut and the area of the remaining card-board.
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
It is proposed to build a single circular park equal in area to the sum of areas of two circular parks of diameters 16 m and 12 m in a locality. The radius of the new park would be ______.
A table top is semicircular in shape with diameter 2.8 m. Area of this table top is ______.
