Probability feels intuitive — until you bet on it. The math is simple; the human brain just doesn't grasp randomness well.
If you have ever stared at a number on a form and wondered where it came from, you are not alone. Probability feels intuitive — until you bet on it. The math is simple; the human brain just doesn't grasp randomness well.
P(event) = favorable outcomes / total outcomes. Coin flip head = 1/2 = 0.5.
P(A and B) = P(A) × P(B). Two coin flips both heads = 1/2 × 1/2 = 1/4.
P(A given B) — the chance of A happening when B already has. Bayes' theorem extends this.
Past coin flips don't affect next ones. 10 heads in a row → next flip still 50/50.
Why is the Monty Hall problem counterintuitive? Because human brains don't update probabilities well after new information.
What's expected value? Weighted average of all outcomes. Used in poker, insurance, business decisions.
Whatever number you land on, sanity-check it against a second method or a quick estimate in your head.