Question

A dinner plate has a circumference of 106.76 cm. What is the area of the dinner plate? Use = 3.14.

Answer 1

c=2pr, r=c/(2p)

a=pr^2, using r found above we get:

a=p(c^2/(4p^2))

a=(c^2)/(4p), since c=106.76 and we approximate pi as 3.14

a=(106.76^2)/(4*3.14)

a=11612.2176/12.56 cm^2

a≈924.54 cm^2 (to nearest one-hundredth of a square cm)