Question

Gareth believes that if he flips a coin 820 times, it will land heads up exactly 410 times. What would you tell Gareth about his prediction?

Answer 1

While 410 heads is the most likely outcome, it is not guaranteed. In fact, purely by chance, the outcome may vary from 410. There is even a very small chance (about 1 in 10^247) that he will get 0 heads. Furthermore, even though 410 is the most likely outcome, it will only occur about 3% of the time. Probability gives an average expectation. It does not guarantee the outcome of any trial.