First, find the side of the square using the surface area.
SA(square) = 6s^2
72 = 6s^2
12 = s^2
s = 2 square root of 3
The formula to get the scale factor is equal to big/small
SF = big / small.
1.5 = 2 square root of 3 / small
4 square root of three = 3s
s = 4 square root of three over 3
SA = 6s^2
SA = 6 (4 square root of three over 3)^3
SA = 288 / 9
SA = 32 in^2