volume of a cylinder

Area of a Circle

• Radius

• Diameter

• Square

• Pi

Multiple Choice

What is the formula for area of a circle given the radius?

• A = πr

• A = 2πr

• A = πd

• A = πr²

Multiple Choice

What does

$$\pi$$  stand for?

• 18.14

• 14.12

• 3.14

• 0

Diameter

a straight line passing from side to side through the center of a body or figure, especially a circle or sphere.

RADIUS

a straight line from the center to the circumference of a circle or sphere.

Example 1

The Radius of this circle is 5 inches. What is the diameter?

Example 2

The DIameter of this circle is 22 centimeters. What is the radius?

Fill in the Blanks

What is the diameter of this circle?

Fill in the Blanks

What is the radius of this circle?

Remember that when you square a whole number, we multiply that number by itself.

See the picture for examples.​

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Squaring Numbers

Multiple Choice

find the area of the circle below.

• 100 cm

• 225 cm

• 9 cm

• 28.26 cm

Multiple Choice

A cruise ship has a large, circular window. It has a diameter of 8 meters.

What is the Radius?

• 8 m

• 16 m

• 64 m

• 4 m

Multiple Select

A cruise ship has a large, circular window. It has a diameter of 8 meters.

Set It Up:

• $$A=4^2\pi$$  

• $$A=4^2\times3.14$$  

• $$A=8\pi$$  

• $$A=64\times3.14$$  

• $$A=8\times8\times3.14$$  

Multiple Choice

A cruise ship has a large, circular window. It has a diameter of 8 meters. What is the window's area?

• 31.25 m²

• 29.55 m²

• 30.36 m²

• 50.27 m²

Volume of a Cylinder

Multiple Choice

What is the EXACT volume of the cylinder?

• $$60\pi\ cm^3$$

• $$120\pi\ cm^3$$

• $$300\pi\ cm^3$$

Multiple Choice

Which is the correct set up for the volume of the cylinder?

• $$V=\pi\times8\times15^2$$

• $$V=\pi\times8^2\times15$$

• $$V=\pi\times8\times15$$

Multiple Choice

What is the approximate area of the cylinder BASE?

• $$50.24cm^2$$

• $$16\pi cm^2$$

• $$36.78cm^2$$

• $$12.56cm^2$$