I guess you mean surface area.
Let V1 and V2 be the volumes of the similar figures respectively.
Let A1 and A2 be the surface areas of the similar figures respectively.
\(\frac{V_1}{V_2}=(scale\space factor)^3=(\frac{length\space of\space a\space side\space of\space V_1}{length\space of\space a\space side\space of\space V_2})^3\)
\(\frac{A_1}{A_2}=(scale\space factor)^2=(\frac{length\space of\space a\space side\space of\space V_1}{length\space of\space a\space side\space of\space V_2})^2\)
\(\therefore (\frac{V_1}{V_2})^2 = (\frac{A_1}{A_2})^3\)
.