Question

2. Find the circumference of a circle whose diameter is 21 cm. don't give unwanted answers give perfect answers​

Answer 1

$\sf \Large Solution!!$

$\sf \to Diameter=21\:cm$

$\sf \to Radius=\dfrac{21}{2}=10.5\:cm$

$\sf \to Circumference=2\pi r$

$\sf \to Circumference=2\times \dfrac{22}{7}\times 10.5\:cm$

$\boxed{\blue{\sf Circumference=66\:cm}}$

Answer 2

Answer:

346.5cm^2 = area

66cm = circumference

Step-by-step explanation:

area of circle = πr^2

πr^2 = (πd^2)/4

= (22/7 × 21 × 21)/4

= 346.5 cm^2

circumference of circle = 2πr

2πr = πd

= 22/7 × 21

= 66cm