So to find out the surface area of the bottom of the pencil holder, we can use the formula for the area of a circle.
A(bottom)=πr²
plug in the data we know
A(bottom)=π6²
A(bottom)=π*36
A(bottom)=36π cm²
For the surface area of the side, we need to find out the circumference of the bottom circle and then multiply that by the height.
A(side)=C*h
C=πd
C=π12
C=12π
A(side)=12π*10
A(side)=120π cm²
Total surface area=36π+120π=156π or 490.09cm²
