Question

if the radius of a pizza pie is 20 cm, what is the price of the pizza per area (cm sq.)?

Answer 1

You have not said how much the pizza costs.

Answer 2

first get the area of circle:
A = pi(r^2)
A = pi(20^2)
A = 400*pi sq. cm

then multiply this to the price of pizza per sq. cm to cancel the sq. cm units and obtain the price of pizza,,

so there,, =)