Circumference and Pi

Front

What is the formula to find the circumference of a circle?

Back

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

Front

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

Back

5 inches.

Front

What is Pi (π)?

Back

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

Front

How do you calculate the diameter if you know the radius?

Back

Diameter = 2 × radius.

Front

What is the circumference of a circle with a radius of 7 cm?

Back

Circumference = 2 × π × 7 cm ≈ 43.98 cm.

Front

What is the relationship between diameter and circumference?

Back

The circumference is π times the diameter.

Front

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

Back

Diameter = Circumference / π ≈ 10 cm.

Front

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

Back

Area = π × (radius)² ≈ 28.27 m².

Front

What is the minimum length of fencing needed for a circular garden with a radius of 15 ft?

Back

Circumference = 2 × π × 15 ft ≈ 94.25 ft.

Front

If a circular pool has a diameter of 16 ft, what is its circumference?

Back

Circumference = π × 16 ft ≈ 50.27 ft.