Area of a Circle

Front

What is the formula for the area of a circle?

Back

The area (A) of a circle is calculated using the formula A = πr², where r is the radius of the circle.

Front

What does the term 'radius' mean in relation to a circle?

Back

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

Front

If a circle has a radius of 4.5 feet, what is its area?

Back

63.585 ft² (using the formula A = πr²).

Front

What is the approximate value of π (pi)?

Back

π is approximately 3.14.

Front

How do you calculate the area of a circle with a radius of 51 feet?

Back

Area = π(51)² ≈ 8167 ft².

Front

What is the area of a circle with a radius of 10 cm?

Back

Area = π(10)² ≈ 314.16 cm².

Front

What is the relationship between diameter and radius?

Back

The diameter is twice the length of the radius (d = 2r).

Front

If the radius of a circle is doubled, how does the area change?

Back

If the radius is doubled, the area increases by a factor of four (A = π(2r)² = 4πr²).

Front

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

Back

Area = π(3)² ≈ 28.27 cm².

Front

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

Back

Area = π(5)² ≈ 78.54 ft².