What would the probability be for the 11th flip to be the same as 10th flip

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Discussion Overview

The discussion revolves around the probability of the 11th flip of a coin being the same as the 10th flip, based on the outcomes of the previous 10 flips. It explores both the scenario of a fair coin and the implications of a potentially biased coin based on historical outcomes.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant seeks a formula to determine the probability of the 11th flip based on the last 10 flips, providing a specific sequence of outcomes.
  • Another participant asserts that, assuming a fair coin, the probability of the 11th flip matching the 10th flip is 1/2, regardless of previous outcomes.
  • A different viewpoint suggests that if the coin is not fair and may be weighted, the outcomes of the first 10 flips could influence the probability of the 11th flip. In this case, the participant calculates a probability of 0.6 for heads and 0.4 for tails based on the previous results.
  • One participant notes that the history of flips does not affect the fairness of future flips, emphasizing that previous outcomes do not "make up" for future results.

Areas of Agreement / Disagreement

Participants express differing views on whether the probability of the 11th flip can be influenced by the outcomes of the previous flips, leading to an unresolved discussion on the implications of a fair versus biased coin.

Contextual Notes

Assumptions about the fairness of the coin and the interpretation of historical data are not fully resolved, and the discussion reflects varying perspectives on how to approach probability in this context.

xNICK1
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I'm wanting to know if there is a formula that can get the probability of then next flip, by taking the data/ averages of the last 10 flips.
So, if the last 10 flips were "H,T,T,H,H,T,T,H,H,H".
What would the probability be for the 11th flip to be the same as 10th flip?
 
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There are two possible outcomes for every toss so that probability would be 1/2. This is different than, say, "What is the probability of tossing two heads in a row?" which would be 1/2 * 1/2 = 1/4.
 
Assuming this is a fair coin, that the probability of "heads" or "tails" is always 1/2, then, pretty much by definition, the probability of heads or tails on the 11th flip is 1/2.

If we are not assuming that, but are considering the possibility that the coin is "weighted" so that one of "heads" or "tails" is more likely than the other, we could consider that "history", the first ten tosses, reflects which is more likely. Here the first ten tosses are "H,T,T,H,H,T,T,H,H,H", 6 heads, and 4 tails, then we would estimate the probability of heads on anyone toss, and in particular, the eleventh toss, is 0.6 and the probability of tails is 0.4.

Notice that, in this scenario, the fact that there are more heads than tails in the 10 tosses means that another head is more likely than another tail. Future tosses will \left(\right)not "make up" for previous tosses.
 
Thanks!
 

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