Question

Find the area of the circular ring whose external and internal diameters are 20 cm and 6 cm, respectively.​

Answer 1

Step-by-step explanation:

area of a circular ring = π( R1 square- R2 square)

where R1 is external radius and R2 is internal radius

R1=20cm

R1 square= 400 cm square

R2= 6cm

R2 square= 36 cm square

π= 3.14159265

area= π(R1 square - R2 square)

=3.14159265(400-36)

=3.14159265(364)

=1143.539 cm square