Let s represent the measure of one edge of a cube. The volume is then s^3 and the surface area is 6s^2. If you triple the measure of the edges, then each edge would measure 3s, so the volume would be (3s)^3 = 27s^3 which is 27 times larger than the original cube. The surface area of the larger cube would be 6(3s)^2 = 6 x 9s^2 which is 9 times larger than the original cube.
