The edge of a cube is 8 cm. If each edge is reduced by 2 times, then how many times will its total surface area decrease?

To find the surface area S, you need to multiply the area of one face (a ^ 2, where a is a side of a face or an edge of a cube) by the number of faces, i.e. by 6.

With a = 8 cm, S = 8 ^ 2 * 6 cm2;

When a is 2 times less, i.e. a = 8/2 = 4 cm, S = 4 ^ 2 * 6 cm2;

In this case, the area will decrease by (8 ^ 2 * 6) / (4 ^ 2 * 6) = 8 ^ 2/4 ^ 2 = 64/16 = 4 times.