Probability & Statistics Calculator
Educational tool for calculating Permutations, Combinations, and Event Probabilities. Shows step-by-step working logic and includes Z-Table references.
Step-by-Step Logic:
About
Understanding probability and statistics is fundamental to fields ranging from data science to risk management. However, the formulas for counting principles like Permutations and Combinations can be confusing for students. This tool serves as both a calculator and a tutor.
Instead of simply outputting a number, it breaks down the 'working out' process. Whether you are calculating how many ways to arrange a deck of cards (Permutations) or how many lottery teams can be picked from a group (Combinations), this tool visualizes the factorials and fractions involved. It also includes a suite for basic set theory probability, handling unions and intersections of events.
Formulas
The foundation of counting is the Factorial:
For probability of two independent events A and B occurring together:
For mutually exclusive events A or B:
Reference Data
| Function | Formula | Description |
|---|---|---|
| Factorial | n! | Product of all positive integers ≤ n. |
| Permutation (Order matters) | nPr = n!(n−r)! | Arranging r items from n distinct items. |
| Combination (Order doesn't matter) | nCr = n!r!(n−r)! | Selecting r items from n distinct items. |
| Union of Events | P(A ∪ B) | Probability of A OR B occurring. |
| Intersection | P(A ∩ B) | Probability of A AND B occurring. |