Probability of an event in n tries

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Discussion Overview

The discussion revolves around calculating the probability of an event occurring at least once in n successive tries, given that the probability of the event occurring in a single try is m/n. The focus includes both the formula derivation and reasoning behind it.

Discussion Character

  • Mathematical reasoning

Main Points Raised

  • One participant asks for the formula to calculate the probability of an event occurring at least once in n tries, given the probability m/n for a single try.
  • Another participant suggests using the formula P=1-(1-p)^n, where p is the probability of the event occurring in one try.
  • A third participant notes that for large n, the expression can be approximated as 1 - e^{-m}, indicating a relationship between the probability and the exponential function.
  • A later reply expresses gratitude for the simplicity of the solution compared to their initial thoughts of calculating the probability for exact occurrences and summing them.
  • The same reply also mentions an interest in removing the dependence of n from the formula.

Areas of Agreement / Disagreement

Participants appear to agree on the formula for calculating the probability of at least one occurrence, but there are varying approaches and thoughts on simplifying the expression, particularly for large n. No consensus on a single method is reached.

Contextual Notes

The discussion does not resolve the implications of the approximation for large n or the potential limitations of the formula in different contexts.

Delta2
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IF the probability for an event to happen in one try is m/n , what is the probability for the event to happen at least one time in n successive tries. In each try the probability of event is m/n.

I care mainly for the formula that I suppose it involves m and n but if you kind enough to provide the reasoning it is welcomed.
 
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If you use the probability ## p ##, the probability it won't happen in ## n ## tries is ## (1-p)^n ## and so the probability of one or more occurrences is ## P=1-(1-p)^n ##.
 
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I'm not sure if it is worth point this out, but for large n

##1 - (1-p)^n = 1 - (1-\frac{m}{n})^n \approx 1 - e^{-m}##
 
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Thanks both I couldn't imagine it was so simple, I was thinking it the hard way (computing the probability for the event to appear exactly k times and then summing from k=1 to n). I also was thinking of a way to remove the dependence of n from the formula, so thanks @StoneTemplePython too.
 
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