The theoretical probability is the mathematical odds.
A coin flip has 50/50 odds, mathematically.
So then you do the experiment and flip a US nickel 10,000 times, recording 5,127 heads and 4,873 tails.
Your measured experimental probability isn’t 50/50, it’s 51/49.
Maybe the nickel is actually slightly unbalanced. Maybe you flip it with a bias. Maybe this is just random variability. If your experimentally measured probability is way different than the theoretical probability, you have to try to explain why. Either the theory is wrong or your experiment was flawed.
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