Question

what happens to the area of a circle if the radius is increased by 10% ?

Answer 1

The area would increase by (1.1)²

Answer 2

The reason? The area of a circle = PI*r²
Let's suppose the radius is 1. If we increase that by 10% the area increases by r²
So, the area gets larger by a factor of (1.1)²

Similarly, what happens to the volume of a sphere if the radius is doubled?
In the formula, the radius of the sphere is cubed, so the volume of the sphere is also cubed.
So, doubling a sphere's radius increases the volume by a factor of 2³ or 8 times.

Answer 3

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