Question

Write an expression in simplest for the volume of the new cube in terms of a.

Answer 1

After decreasing the sidelength to 20% of the original size, the new sidelength is:

$0.20a$

The volume of a cube is given by the product of 3 of its sidelengths, it means, that the volume of the cube is the sidelength raised to 3:

$V=(0.20a)^3=0.008a^3$