Area of Circles

Front

What is the formula for finding the area of a circle?

Back

A = π·r²

Front

If you are given the diameter, how can you calculate the radius?

Back

Divide the diameter by 2

Front

What is the value of π (pi) approximately?

Back

3.14

Front

How do you find the diameter of a circle if you know the radius?

Back

Multiply the radius by 2

Front

What is the area of a circle with a radius of 7 cm? (Use π = 3.14)

Back

A = π·r² = 3.14·(7)² = 153.86 cm²

Front

What is the area of a circle with a diameter of 10 cm? (Use π = 3.14)

Back

A = π·r² = 3.14·(5)² = 78.5 cm²

Front

What is the relationship between the radius and diameter of a circle?

Back

The diameter is twice the radius.

Front

If the area of a circle is 314 cm², what is the radius? (Use π = 3.14)

Back

r = √(A/π) = √(314/3.14) = 10 cm

Front

What is the area of a circle with a radius of 10 m? (Use π = 3.14)

Back

A = π·r² = 3.14·(10)² = 314 m²

Front

How do you convert the area from square centimeters to square meters?

Back

Divide the area in cm² by 10,000.