Question

A cube has side length a. The side lengths are decreased to 40% of their original size. Write an expression in simplest form for the volume of the new cube in terms of a.

Answer 1

$V=a ^{3}$ originally. Then you reduces the side lengths a so it will be$V=( \frac{2}{5} a)^{3} = \frac{8}{125}a^{3}$
Just note that 40% is the same as 2/5.<span />