Respuesta :

Answer: 720 ways

Step-by-step explanation:

We know that the total number of ways to arrange n things in a row in order is given by Permutations.

i.e. The total number of ways to arrange n things in a row= n!

Therefore, the number of ways to arrange 6 unique CD's in order along a shelf will be :

[tex]6!=6\times5\times4\times3\times2\times1=720[/tex]

Hence, there are 720 ways to arrange 6 unique CD's in order along a shelf.