Answer:
63 = number of blocks needed
Step-by-step 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