what is the area of a circle with a circle inscribed?

Question

A circular table witha diameter of 4 feet has four circular place mats on it, each with a diameter of 6 inches. what is the area of the table in inches, not covered with the place mats?

Answer 1

Serkel area=pi*rad*rad

tabel diameter=4 ft, so radius=2 ft or 24 inch

Area=4*pi=4*3.14159265

tabel area=12.5663706 ft^2

4 mats=serkels with diameter=6 inch, so radius=3 inch=(1/4) ft

mat area=4*pi*(1/4)*(1/4)

=0.25*pi=0.785398162

tabel area - mat area=11.78097244