Circle Unit Review

Front

What is the formula for the circumference of a circle?

Back

Circumference = 2πr, where r is the radius.

Front

What is the relationship between diameter and radius?

Back

Diameter = 2 × Radius.

Front

How do you calculate the area of a circle?

Back

Area = πr², where r is the radius.

Front

If a circle has a radius of 4, what is its diameter?

Back

Diameter = 8.

Front

What is the circumference of a circle with a radius of 4?

Back

Circumference = 8π or about 25.12.

Front

What is the area of a circle with a diameter of 8?

Back

Area = 16π or about 50.24.

Front

How many feet are in a diameter of 20 feet?

Back

The diameter is 20 feet.

Front

If a circle has a diameter of 118 feet, what is its radius?

Back

Radius = 59 feet.

Front

What is the approximate area of a circle with a diameter of 118 feet?

Back

Area ≈ 10,930.34 ft².

Front

How many steps would it take to walk around a circular lawn with a circumference of 148 feet?

Back

Approximately 236 steps.