Q.1 Find the circumference of the circles with the following radius. (Take \(\pi =\frac{22}{7} \))
(a) 14 cm
(b) 28 mm
(c) 21 cm

(a) Given: Radius (r) = 14 cm
Circumference =\( 2\pi r = 2 × \frac{22}{7} × 14 = 88 cm \)
(b) Given: Radius (r) = 28 mm
Circumference =\( 2\pi r = 2 × \frac{22}{7} × 28 = 176 mm \)
(c) Given: Radius (r) = 21 cm
Circumference = \( 2\pi r = 2 × \frac{22}{7} × 21 = 132 cm \)