Question

The diameters of two solid spheres are in the ratio 5 : 7. The ratio between areas of their curved surfaces is ______.

Options

• 5 : 7

• 7 : 5

• 49 : 25

• 25 : 49

Answer 1

The diameters of two solid spheres are in the ratio 5 : 7. The ratio between areas of their curved surfaces is 25 : 49.

Explanation:

The surface area of a sphere is proportional to the square of its radius or diameter (4πr² or πd²). Given the ratio of the diameters is 5 : 7, the ratio of their curved surface areas is 5² : 7² = 25 : 49.