CASECS2 / FREE TOOL
At least one success: an educational probability example
Enter a probability per hypothetical attempt and a number of independent attempts with the same probability.
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- At least one success, %
- 65.13215599
How to use this example
Probability of at least one success = 1 − (1 − p / 100)^n. For 50% and 2 independent attempts, the result is 75%.
Meaning and limits
Independence and the same probability are assumptions. This is not a game quote, a promise of success, an expected profit or a way to recover losses. Previous failures do not make the next independent attempt more likely to succeed.
Steps
- Enter your assumptions Enter a probability per hypothetical attempt and a number of independent attempts with the same probability.
- Calculate again Probability of at least one success = 1 − (1 − p / 100)^n. For 50% and 2 independent attempts, the result is 75%.
- Check real conditions Independence and the same probability are assumptions. This is not a game quote, a promise of success, an expected profit or a way to recover losses. Previous failures do not make the next independent attempt more likely to succeed.
Fields and allowed values
Enter a probability per hypothetical attempt and a number of independent attempts with the same probability.
| Field | Minimum | Maximum |
|---|---|---|
| Success probability per attempt, % | 0 | 100 |
| Number of attempts | 1 | 500 |
Sources and scope
Original CASECS2 calculator prepared with AI assistance. Examples are checked against the maintained model. Provider prices, fees and commercial availability are not loaded automatically.
This is a free reference calculation. It does not execute payments or games. A shared result is a historical user-entered example, not a current quote.