Question

The radii of two concentric circles are 19 cm and 16 cm respectively. The area of the ring enclosed by these circles is

Options

• 320 cm²

• 330 cm²

• 332 cm²

• 340 cm²

Answer 1

330 cm² 

Let ; 

R = 19 cm and r = 16 cm

Thus, we have ;

Area of the ring = π(R² - r²)

= π (R + r) (R - r)

`= |22/7xx(19+16)xx(19-16)|"cm"^2`

`=(22/7xx35xx3)"cm"^2`

= 330 cm²