Circle Measurements and Calculations

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Questions and Answers

The distance around a circle is called its?

Diameter

Area

Circumference (correct)

Radius

The distance across a circle through its center is called?

Diameter

The __________ of a circle is the distance from the center of a circle to any point on the circle.

radius

If the radius of a circle is 2 inches, what is the diameter?

Diameter = 4 in Signup and view all the answers

If the diameter of a circle is 3 centimeters, what is the circumference?

Circumference = 9.42 cm Signup and view all the answers

If the radius of a circle is 2 inches, what is the circumference?

Circumference = 12.56 in Signup and view all the answers

What is the diameter if the radius of a circle is 15.3 centimeters?

Diameter = 30.6 cm Signup and view all the answers

Find the circumference of a circle with a diameter of 7.5 inches.

Circumference = 23.55 Signup and view all the answers

A _________________ is a part of a line that is bounded by two endpoints.

line segment Signup and view all the answers

If the diameter of a circle is 8 centimeters, what is the area?

Area = 50.24 cm Signup and view all the answers

If the radius of a circle is 3 inches, what is the area?

Area = 28.26 in Signup and view all the answers

If the radius of a circle is 9 centimeters, what is the area?

Area = 254.34 cm Signup and view all the answers

If the diameter of a circle is 12 inches, what is the area?

Area = 113.04 in Signup and view all the answers

If the radius of a circular rug is 4 feet, what is the area?

Area = 50.24 feet Signup and view all the answers

If the diameter of a bicycle wheel is 20 inches, what is the area of the wheel?

Area = 314 Signup and view all the answers

What is the formula for the area of a circle?

A = πr^2 Signup and view all the answers

What is the area of a circle with a radius of 3 m?

Area = 28.27 m² Signup and view all the answers

What is a line that links two points on a circle?

Chord Signup and view all the answers

What is the diameter of a circle with a radius of 7 inches?

The diameter of a circle is 14 inches Signup and view all the answers

What is the area of a circle if its diameter is 10 centimeters?

Area = 78.5 centimeters Signup and view all the answers

Study Notes

Circle Measurements and Definitions

Circumference is the distance around a circle.
Diameter is the distance across a circle through its center.
Radius is the distance from the center of a circle to any point on the circle.

Relationship Between Diameter and Radius

Diameter is twice the radius (d = 2r).
For a radius of 2 inches, the diameter is 4 inches.
For a radius of 15.3 centimeters, the diameter is 30.6 centimeters.

Calculating Circumference

Circumference can be calculated using the formula: C = πd or C = 2πr.
For a diameter of 3 centimeters, the circumference is approximately 9.42 cm.
For a radius of 2 inches, the circumference is approximately 12.56 inches.
For a circle with a diameter of 7.5 inches, the circumference is approximately 23.55 inches.

Calculating Area

Area of a circle is calculated using the formula: A = πr².
An 8-centimeter diameter circle has an area of approximately 50.24 cm².
A circle with a radius of 3 inches has an area of approximately 28.26 in².
For a radius of 9 centimeters, the area is approximately 254.34 cm².
A circular rug with a radius of 4 feet has an area of approximately 50.24 feet².
A bicycle wheel with a diameter of 20 inches has an area of approximately 314 in².

Specific Area Calculations

For a diameter of 10 centimeters, the area is approximately 78.5 cm².
The area calculations demonstrate that the area increases with both radius and diameter measurements.

Additional Geometry Terms

A line segment is a part of a line bounded by two endpoints.
A chord is a line that links two points on the circumference of the circle.

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Description

Test your knowledge on circle measurements, including circumference, diameter, radius, and area calculations. This quiz will cover essential formulas and relationships between these properties. Perfect for students looking to reinforce their understanding of geometry.