Area and Circumference Flashcard

Front

What does 'circumference' mean?

Back

Distance around a circle.

Front

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

Back

Circumference = 2 × π × radius.

Front

What is the radius of a circle?

Back

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

Front

What is the diameter of a circle?

Back

The distance across the circle through its center, equal to twice the radius.

Front

What is the formula to calculate the area of a circle?

Back

Area = π × radius².

Front

If the radius of a circle is 9 meters, what is the circumference using π = 3?

Back

Circumference = 2 × 3 × 9 = 56.52 meters.

Front

If the diameter of a circle is 10 cm, what is the area using π = 3?

Back

Area = 3 × (5)² = 78.5 cm².

Front

What is the relationship between radius and diameter?

Back

Diameter = 2 × radius.

Front

If a circle has a circumference of 28.26 cm, what is its radius using π = 3?

Back

Radius = Circumference / (2 × π) = 28.26 / 6 = 4.71 cm.

Front

What is the circumference of a circle with a radius of 7 cm using π = 3?

Back

Circumference = 2 × 3 × 7 = 42 cm.