Tom has some cubes that are 2 cm. on each side. How many of them will fit into a box that is a cube with each side 4 cm. long?

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To determine how many cubes will fit inside the larger cube, you need to calculate the volume of each cube and the volume of the larger cube.

The volume of a cube is calculated by cubing the length of its side. So, the volume of the smaller cube is 2 cm * 2 cm * 2 cm = 8 cm^3.

Similarly, the volume of the larger cube is 4 cm * 4 cm * 4 cm = 64 cm^3.

To find out how many smaller cubes will fit inside the larger cube, divide the volume of the larger cube by the volume of the smaller cube: 64 cm^3 / 8 cm^3 = 8.

Therefore, you can fit 8 smaller cubes with 2 cm sides into the larger cube with 4 cm sides.