This worksheet is about finding the circumferences of circles.
The circumference of a circle is its perimeter or the distance around its edge.
You must learn these two important formulae for a circle of radius, r or diameter, d:
Circumference of a circle = 2πr
Circumference of a circle = πd
Find the circumference of a circle of radius 6 cm.
Circumference = 2 × π × r = 2 × π × 6 = 12 × π = 37.7 cm (1 dp)
Find the circumference of a circle of diameter 6 cm.
Circumference = π × d = π × 6 = 18.8 cm (1 dp)
You can always use an online scientific calculator for this activity if you don't have a physical calculator to hand.