The Probability Calculator is a multi-functional tool designed to solve a variety of common probability problems. It's an excellent resource for students learning the fundamentals of probability, as well as for anyone needing to make quick probability calculations. The calculator is organized into three distinct tabs for different types of problems. The 'Single Event' tab is for calculating basic probability. Here, you need to enter the 'Favorable Outcomes' (the number of ways an event you're interested in can happen) and the 'Total Outcomes' (the total number of all possible outcomes). The tool will then calculate the probability of the event, expressed as a percentage and a fraction. For example, to find the probability of rolling a 4 on a six-sided die, you would enter 1 favorable outcome and 6 total outcomes. The 'Independent Events' tab is for problems involving two separate events that do not affect each other. You need to enter the probability of each event occurring, 'P(A)' and 'P(B)', as a decimal (e.g., 0.5 for 50%). The calculator will then compute two results: the probability of both events happening together, 'P(A and B)', and the probability of at least one of the events happening, 'P(A or B)'. The 'Normal Distribution' tab is for working with the most common continuous probability distribution. To find the cumulative probability—that is, the probability of a random variable X being less than or equal to a specific value x, or P(X ≤ x)—you need to provide the 'Mean (μ)' and 'Standard Deviation (σ)' of the distribution, along with the specific 'Value (x)' you are interested in. The tool will then calculate this cumulative probability, which is crucial for statistical analysis and hypothesis testing.