Answer:
The number of selections of collars that are possible if repetition of colors are not allowed is;
![336\text{ selections}](https://img.qammunity.org/2023/formulas/mathematics/college/q4lz1rii8xl161eio2k7vlk1hqlx9w3l37.png)
Step-by-step explanation:
Given that Paul wants to buy a new collar for each of his 3 dogs.
And The collars come in a choice of 8 different colors.
The number of ways of selections of collars without repetition can be written as;
![P=(n!)/((n-r)!)](https://img.qammunity.org/2023/formulas/mathematics/high-school/m6bem3f0fl350db11jl56i21ppsfb0tv1u.png)
![\begin{gathered} C=(8!)/((8-3)!)=(8!)/(5!) \\ C=8*7*6 \\ C=336 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/i7wfybo7kex1himzwwhoyryll9i21urz84.png)
Therefore, the number of selections of collars that are possible if repetition of colors are not allowed is;
![336\text{ selections}](https://img.qammunity.org/2023/formulas/mathematics/college/q4lz1rii8xl161eio2k7vlk1hqlx9w3l37.png)