Does the area of a circle double if its diameter doubles?

Answer 1

The area is four times as large if the diameter doubles.

The area of a circle is A = (pi)r2 or (pi)(diameter/2)2

Since d is squared, it increases the area by the square of 2 if the diameter is doubled.

Try calculating the area for a diameter of 2m, 4m and 8m to prove this.