**Probability theory** plays a crucial role in **stock market investments** by helping investors **assess the risk and reward** associated with different investment options. By analyzing historical data, market trends, and other relevant information, probability theory allows investors to estimate the likelihood of different outcomes, such as potential gains or losses. This information empowers investors to make more informed decisions based on their risk tolerance and investment goals. However, it's important to note that probability theory cannot **accurately predict future stock prices**, **eliminate investment risk**, or **guarantee investment success**. The stock market is inherently unpredictable, and probability theory serves as a tool for understanding and managing risk, not eliminating it.