Question

Tess makes a circular flower bed of diameter 4 metres. She puts a single line of paving blocks around the outside of the flower bed. Each block is 20cm in length. How many blocks does she need to go around the whole flower bed?

Answer 1

63 = number of blocks needed

Explanation:

Circumference = 2 • ∏ • radius

radius = diameter/2

radius = 4m/2

radius = 2m

Circumference = 2 • π • 2m

Circumference = 2 • π • 2m

Circumference = 4 • π m

Circumference = 12.6m

Circumference = 1260cm

1260cm / 20cm = number of blocks needed

63 = number of blocks needed