3 Event Probability Calculator
3 Event Probability Calculator helps determine the probability of three independent events occurring together. It's essential for risk assessment, statistical analysis, and decision-making in fields like finance, engineering, and research.
Formula Used
P(A ∪ B ∪ C) = P(A) + P(B) + P(C) - P(A∩B) - P(A∩C) - P(B∩C) + P(A∩B∩C))
How to Use
1. Enter probabilities (0-1) for each event
2. Click Calculate
3. View combined probability result
4. Use Clear to reset
Event B:
Event C:
FAQ 1: What is a 3-event probability calculator?
A tool that calculates the probability of three events occurring individually or in combination, considering both independent and dependent events through mathematical probability principles.
FAQ 2: Can this handle overlapping events?
Yes, the formula accounts for overlapping probabilities through inclusion-exclusion principle, automatically adjusting for double-counted intersections between events.
FAQ 3: Are decimal inputs accepted?
Yes, enter probabilities as decimals between 0-1 (e.g., 0.25 for 25%). The calculator supports two decimal places for precision.
FAQ 4: What if events are mutually exclusive?
For mutually exclusive events, the calculator will automatically exclude intersection probabilities since they can't occur simultaneously.
FAQ 5: How accurate are the results?
Results are mathematically precise when using valid probability inputs and assuming correct understanding of event relationships (independence/dependence).
FAQ 6: Can I use percentages instead?
Convert percentages to decimals (e.g., 75% = 0.75) before inputting. The calculator only accepts decimal values between 0 and 1.
FAQ 7: What's the maximum allowed value?
All inputs must be ≤1. The calculator validates entries and will alert if values exceed probability range limits.
FAQ 8: Does it handle dependent events?
This version assumes independent events. For dependent events, manual calculation of conditional probabilities is required first.
FAQ 9: Why include intersection terms?
Intersections prevent double-counting overlapping probabilities. The formula adds back the triple intersection that was subtracted too many times.
FAQ 10: Can I calculate AND probabilities?
For combined AND probability (all events occurring), multiply individual probabilities: P(A) × P(B) × P(C). This calculator focuses on OR probabilities.