Question

In the figure OA = 7cm, OB = 14cm and
(Kindly refer to the image)

Answer 1

Answer:

Given: Radius of inner circle =7 cm

Radius of outer circle =14 cm

Angle made by sector = 40

o

Area of sector OAC =

360

o

40

o

×πr

2

=

9

1

××

7

22

×14

2

=68.44

Area of sector OBD =

360

o

40

o

×πr

2

=

9

1

××

7

22

×7

2

=17.11

Area of the small region ABDC

= Area of the small sector OAC – Area of the small sector OBD =(68.44−17.11)cm

2

Area of shaded region ABDC= Area of outer circle − Area of inner circle − area of small region ABCD

Area of shaded region ABDC=π×14

2

−π×7

2

−(68.44−17.11)cm

2

Area of shaded region ABDC=410.484 cm

2

Step-by-step explanation:

Given: Radius of inner circle =7 cm

Radius of outer circle =14 cm

Angle made by sector = 40

o

Area of sector OAC =

360

o

40

o

×πr

2

=

9

1

××

7

22

×14

2

=68.44

Area of sector OBD =

360

o

40

o

×πr

2

=

9

1

××

7

22

×7

2

=17.11

Area of the small region ABDC

= Area of the small sector OAC – Area of the small sector OBD =(68.44−17.11)cm

2

Area of shaded region ABDC= Area of outer circle − Area of inner circle − area of small region ABCD

Area of shaded region ABDC=π×14

2

−π×7

2

−(68.44−17.11)cm

2

Area of shaded region ABDC=410.484 cm

2