Question

The diameter of a penny is 19.05 mm and the thickness is 1.52 mm what is the approximate volume of the role of Penny to the nearest 10th

Answer 1

The volume of a cylinder is the area of the base circle times the height.

The area of a circle is $\pi r^2$. Since the diameter is 19.05, the radius will be half that diameter:

$r=\dfrac{d}{2}=\dfrac{19.05}{2}=9.525$

So, the base area is

$A=\pi(9.525)^2$

Multiply this by the thickness and you'll get the volume.