Answer :

Given:

Mr Korber owns 8 pairs of shoes.

To find:

The number of ways that he chooses 4 pairs of shoes.

Explanation:

Using the combination rule,

[tex]\begin{gathered} ^8C_4=\frac{8!}{(8-4)!4!} \\ =\frac{8!}{4!4!} \\ =\frac{4!\times5\times6\times7\times8}{4!\times4\times3\times2\times1} \\ =5\times2\times7 \\ =70\text{ ways} \end{gathered}[/tex]

Thus, he can choose 4 pairs of shoes out of 8 pairs of shoes in 70 ways.