Question

What is the surface area of a cylinder with base radius 4 and height 7?Either enter an exact answer in terms of \pi or use 3.14 for \piπpi and enter your answer as a decimal

Answer 1

112π cubic units

Explanation:

The volume of a cylinder is the area of the base × height.

The area of a circle is πr to the 2nd power

So the area of the base is π × 4 to the second power = 16π

The height of the cylinder is 7, so the volume is 16π × 7 = 112π cubic units

Answer 2

The surface area is 88*pi square units.

Explanation:

The surface area of a cylinder is given by two times the area of the base plus the area of the sides. This is given bellow:

surface area = 2*(base area) + (side area)

base area = pi*r²

base area = pi*(4)²

base area = pi*16 = 16*pi

side area = 2*pi*r*h

side area = 2*pi*4*7

side area = 8*7*pi

side area = 56*pi

surface area = 2*(16*pi) + 56*pi

surface area = 32*pi + 56*pi

surface area = 88*pi

The surface area is 88*pi square units.