Question

AD is the diameter of a circle of radius 6 cm and AB =BC =CD. Semi circles are drawn with AB and BD as diameters. Find the perimeter and area of the shaded region. ​

Answer 1

Radius=6cm

so diameter=12cm

we know ab=bc=cd

so 12/3=4cm

area of perimeter of upper semicircle

=(2*22*radius/14)+diameter

=18.85+12

=30.85cm

perimeter of shaded region in lower circle

=(2*22*radius/14)+diameter

=6.28+4=10.28cm

peimeter of unshaded region in upper circle

=(2*22*radius/14)+diameter

=12.57+8=20.57

perimeter of shaded portion=perimeter of shader region in upper circlr+perimeter of shader region in lower circle

=(30.85-20.57)+10.28

=10.28+10.28

=20.56