Question

Find the area of a circular ring who’s inner and outer diameter are 20 m and 22 m respectively

Answer 1

Ok
Area of ring with outer diameter =πr^2
where radius = 11m so
area = 380.2mm
Area with inner diameter = 314.2mm
Area of ring = 380.2 - 314.2
which = 66sq. mm
hope u like it

Answer 2

$<b>Radius = Diameter / 2</b>$

Inner Diameter, D1 = 20 cm

Inner radius, R1 = 20 / 2 = $<u>10 cm</u>$

Outer Diameter, D2 = 22 cm

Outer radius, R2 = 22 / 2 = $<u>11 cm</u>$

Area of the circular ring –

= π ( R2² - R1² )

= 22 / 7 × ( 11² - 10² )

= 22 / 7 ( 121 - 100 )

= 22 / 7 × 21

= 66

$<b><i><u>Area of circular ring = 66 cm².</b></i></u>$