If the diameter of circle C is 3 times greater than the diameter of circle D, how many times greater is the area of circle C compared to circle D?

To determine how many times greater the area of circle C is compared to circle D, we first need to understand the relationship between the diameters and the areas of the circles.

Let’s define the diameter of circle D as d. This means the diameter of circle C, which is stated to be 3 times greater than that of circle D, will be:

Diameter of circle C = 3d

The formula for the area A of a circle is given by:

A = πr²

Where r is the radius of the circle. The radius is half of the diameter, so we have:

Radius of circle D, rD = d/2

Radius of circle C, rC = (3d)/2

Next, we can calculate the areas of both circles:

Area of circle D:

AD = π(rD)² = π(d/2)² = π(d²/4)

Area of circle C:

AC = π(rC)² = π((3d)/2)² = π(9d²/4)

Now, we can find the ratio of the areas of circle C to circle D:

Ratio = AC / AD = (π(9d²/4)) / (π(d²/4))

The π and (d²/4) terms cancel out, leading to:

Ratio = 9

This means that the area of circle C is 9 times greater than the area of circle D.

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