You will use this number to determine how many shares you can buy, which in this case is up to, but not more than 333. Most people don't like to do odd lots, so would round down to 300. Never round up because then you throw the risk control out the window. I try to be conservative in my risk management. I want to make sure I'll be around to play tomorrow.
Risk control is essential.
If you personalize losses, you can't trade. The best traders have no ego. You have to swallow your pride and get out of the losses. Keeping your risk small and constant is absolutely critical. While all of these guys have different methods for making money, each of them agrees that risk control is the single most important aspect of trading.