Probability
Find the probability of an event with equally likely outcomes.
Inputs
Use the units shown—
Enter your values and select Calculate.
Formula & explanation
P(E) = favourable outcomes ÷ total outcomes
Variables & units
- Favourable outcomes
- Numeric value · minimum 0, maximum 1000000
- Total outcomes
- Numeric value · minimum 1, maximum 1000000
Worked example
3 favourable outcomes out of 6 equally likely outcomes gives 0.5.
Assumptions
This counting formula assumes equally likely elementary outcomes.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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