All cubes have 6 faces
Original cube: Edge length = 6 cm. 6 * 6 = 36 cm^2 for one face. 36*6 = 216 cm^2 for the entire cube
New cube (enlarged by a scale factor of 4): 6 * 4 = 24. 24 * 24 = 576 cm^2 for one face. 576 * 6 = 3456 cm^2 for the entire cube
216:3456. 3456 is divisible by 216 which means 3456/216 = 16
This means that the ratio between the enlarged cube and the original cube is 16:1.