radius, diameter, Circumference

Front

What is the radius of a circle?

Back

The radius is the distance from the center of the circle to any point on its circumference.

Front

What is the diameter of a circle?

Back

The diameter is a line segment that passes through the center of the circle and connects two points on its circumference. It is twice the length of the radius.

Front

What is the formula for calculating the circumference of a circle?

Back

Circumference = 2 × π × radius or Circumference = π × diameter.

Front

If the radius of a circle is 3 feet, what is the diameter?

Back

Diameter = 2 × radius = 2 × 3 feet = 6 feet.

Front

If the diameter of a circle is 10 inches, what is the radius?

Back

Radius = diameter ÷ 2 = 10 inches ÷ 2 = 5 inches.

Front

What is π (pi)?

Back

π (pi) is a mathematical constant approximately equal to 3.14, representing the ratio of the circumference of a circle to its diameter.

Front

How do you find the circumference of a circle with a radius of 4 inches?

Back

Circumference = 2 × π × radius = 2 × 3.14 × 4 inches = 25.12 inches.

Front

What is the relationship between diameter and circumference?

Back

The circumference of a circle is directly proportional to its diameter, expressed as C = π × D.

Front

If a circle has a circumference of 31.4 inches, what is its diameter?

Back

Diameter = Circumference ÷ π = 31.4 inches ÷ 3.14 = 10 inches.

Front

What is the area of a circle with a radius of 2 feet?

Back

Area = π × radius² = 3.14 × (2 feet)² = 12.56 square feet.