Probability of repeated events
Independent trials: at least one success, no successes, and expected counts.
- Probability
Over 20 independent trials
Probability of one event5%
Odds of one event1 in 20
No occurrences35.84859224%(1 − p)ⁿ
At least one occurrence64.15140776%1 − (1 − p)ⁿ
Expected number of occurrences1np
Standard deviation0.974679√(np(1−p))
Trials for a 50% chance13.5134
Trials for a 95% chance58.404