Question

A cylinder has a height that is twice the length of the diameter. The diameter of the cylinder is 10 centimeters. What is the surface area of the cylinder?
Type the correct answer in the box. Use numerals instead of words.

The surface area is square centimeters.

Answer 1

Answer:

Step-by-step explanation:

Givens

pi = 3.14

d = 10 cm

h = 2*d

Formula

• The top of the cylinder is a solid circle. So the area of the circle is pi r^2
• There is both a top and bottom to the circle so the fomula is 2*pi*r^2

• The surrounding area of the cylinder is the circumference of the circle times the height. The circumference of the circle is 2*pi*r.
• Then you just multiply by the height.
• formula = 2*pi * r * h

The combined formula is given below.

SA = 2*pi*r^2  +  2*pi*r * h

Conversions

d = 10 cm

h = 2*10

h = 20 cm

r = d/2

r = 10 / 2

r = 5cm

Solution

SA = 2*pi*r^2  +  2*pi*r * h

SA = 2*3.14*5^2 + 2*3.14*5*20

SA = 157 + 628

SA = 785 cm^2

Answer: The surface area is 785 cm^2