How we worked it out
Updated as you change the numbers.
- Both = P(A) × P(B). Either = P(A) + P(B) − P(A)P(B). Neither = (1 − P(A))(1 − P(B)).
Method and assumptions
For independent events the probability that both happen is the product. The binomial distribution counts successes in a fixed number of independent tries with the same chance each time.
Questions
What is the chance of at least one six in four rolls of a die?
1 − (5/6)⁴ ≈ 51.77%.
Sources
Method and figures checked on . Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.