Question

Chloe has 20 unit cubes.How many different rectangular prisms can she build with the cubes?

Answer 1

If she uses all the cubes, its is 12. 
1.  One that is 20x1x1 cubes (20 is length, 1 is width, and 1 is height)
2. One that is 1x20x1 cubes
3. One that is 1x1x20 cubes
4. One that is 4x5x1 cubes
5. One that is 5x1x4 cubes
6. One that is 1x4x5 cubes
7. One that is 10x1x2 cubes
8. One that is 1x2x10 cubes
9. One that is 2x10x1 cubes
10. One that is 2x2x5 cubes
11. One that is 5x2x2 cubes
12. One that is 2x5x2 cubes

Answer 2

Chloe has 20 unit cubes

No. of different rectangular prisms can she build with the cubes = ?

The number of combinations that are possible are as follows:

20 * 1 * 1

1 * 1 *20

1 * 20 * 1

4 * 5 * 1

5 * 4 *1

1 * 5 *4

1* 4 * 5

1 * 10 * 20

20 * 10 * 1

20 * 1 *10

5 * 2 * 2

2 * 5 * 2

These are the 12 possible ways