Area of Circles

Front

What is the diameter of a circle?

Back

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

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

How do you calculate the area of a circle?

Back

Area = π × radius² (A = πr²).

Front

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

Back

The diameter is 20 yards.

Front

If the diameter of a circle is 30 meters, what is the radius?

Back

The radius is 15 meters.

Front

What is π (pi)?

Back

π (pi) is a mathematical constant approximately equal to 3.14, used in calculations involving circles.

Front

What is the area of a circle with a radius of 5 cm?

Back

Area = π × (5 cm)² = 78.54 cm².

Front

What happens to the area of a circle if the radius is doubled?

Back

The area increases by a factor of four.

Front

If the radius of a circle is 7 inches, what is the area?

Back

Area = π × (7 inches)² ≈ 153.94 inches².

Front

What is the relationship between diameter and radius?

Back

The diameter is always twice the radius.