Problema Solution
To make a compact disk, a machine creates a circular disc with diameter 120 mm and then punches a center hole with a diameter 15 mm. When the hole is punched, what fraction of the original.area is removed? Express your answer as a common
Answer provided by our tutors
The original area is:
A1 = (120/2)^2 pi
A1 = 3,600pi
The area of the hole is:
A2 = (15/2)^2pi
A2 = 56.25pi
To find what fraction is removed we divide A1 by A2:
3,600pi/56.25pi =3600/56.25 = 64
1/64 of the original area is removed.