Suppose the sphere below with radius r has a surface area equal to 45 units 2 Find the surface area of the sphere with twice the radius'?

Answer 1

The area of a sphere is given by the formula A = 4πr²

A sphere with radius r has an area = 4πr²

A sphere with radius 2r has an area = 4π(2r)² = 4π.4r² = 16πr²

The ratio of the larger sphere to the smaller = 16πr² : 4πr² = 4 : 1

If the area of the smaller sphere is 45 units then the area of the larger sphere is 45 x 4 = 180 units.