Question

12. A rectangular sheet of metal measuring 50 cm by 30 cm has a semicircle of radius 15 cm cut
from each short side as shown in Fig. 16.27. Find the perimeter of the shape that is left.
13. A bicycle wheel has a radius of 2​

Answer 1

Answer:

Diameter of largest circle=length of the smallest side of rectangle

Area of rectangle=l×b=30×20=600cm

2

Area of circle=πr

2

=π(

2

d

)

2

=π×(

2

20

)

2

=314.16cm

2

Remaining area=600−314.16=285.84cm

2

.