1 Answers
Option 3 : 1 : 2
We know that, volume of a cube = (side)3
∴ Volume of larger cube = 33 = 27 unit3
And, volume of one smaller cube = 13 = 1 unit3
Number of smaller cubes used = Volume of larger cube/Volume of one smaller cube
∴ Number of smaller cubes used = 27/1 = 27
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We know that, a cube has 6 faces.
∴ Total number of faces of all smaller cubes = 6 × 27 = 162
Number of faces of smaller cubes visible on one face of larger cuve = 9
∴ Total number of visible faces of smaller cubes = 9 × 6 = 54
∴ Total number of faces that are not visible = 162 – 54 = 108
∴ required ratio = 54 : 108 = 1 : 2