A bag contains 4 white and 6 black balls. Three balls are drawn at random from the bag. Let $X$ be the number of white balls, among the drawn balls. If $\sigma ^ { 2 }$ is the variance of $X$, then $100 \sigma ^ { 2 }$ is equal to $\_\_\_\_$.
A bag contains 4 white and 6 black balls. Three balls are drawn at random from the bag. Let $X$ be the number of white balls, among the drawn balls. If $\sigma ^ { 2 }$ is the variance of $X$, then $100 \sigma ^ { 2 }$ is equal to $\_\_\_\_$.