✔ 最佳答案
There are altogether 4x3x2= 24 possible combination of putting the cubes into the holes, or you can simply list out all combinations as follows :
1 2 3 4
1 2 4 3
1 3 2 4
1 3 4 2
1 4 2 3
1 4 3 2
2 1 3 4
2 1 4 3
2 3 1 4
2 3 4 1
2 4 1 3
2 4 3 1
3 1 2 4
3 1 4 2
3 2 4 1
3 2 1 4
3 4 1 2
3 4 2 1
4 1 2 3
4 1 3 2
4 2 1 3
4 2 3 1
4 3 1 2
4 3 2 1
Among those, you can find only the following combinations fulfill the requirement that every cube is in the wrong hole :
2 1 4 3
2 3 4 1
2 4 1 3
3 1 4 2
3 4 1 2
3 4 2 1
4 1 2 3
4 3 1 2
4 3 2 1
So there are totally 9 combination fulfilling the requirement.
P (every cube is in the wrong hole)
=9/24
=3/8
=0.375