8. A box contains 5 white balls and 5 black balls. Now, the 10 balls are taken out one by one, ensuring that after each ball is taken out, the number of black balls left in the box is not less than the number of white balls. Assuming balls of the same color are indistinguishable, there are $\qquad$ ways to do this.
$\begin{array}{l}\text { 8. } 42 . \\ C_{10}^{5}-C_{10}^{6}=42 .\end{array}$

The translation is as follows:

$\begin{array}{l}\text { 8. } 42 . \\ C_{10}^{5}-C_{10}^{6}=42 .\end{array}$

Note: The mathematical notation and numbers are universal and do not require translation. The text "8. 42." and the equation are kept the same in the translation.