Probability

Probabilities that are dependent are multiplied

Probabilities that are not dependent are added

$Probability(X)=\frac{Number Of Combinations With X}{TotalNumberOf Combinations}$

$N={t\choose n}=\frac{t!}{(t-n)!\times(n)!}$

t = total number of occurrences, n = number of occurrences

$P={t\choose n}\times(c)^n\times(1-c)^{t-n}$ (with putting back)

t = total number of occurrences, n = number of occurrences, c = probability on single occurrence

$P=\frac{{z\choose a }\times{x\choose b}\times{y \choose c}}{t\choose n}$ (without putting back)

t = total number of occurrences, n = number of occurrences, t = z + x + y, n = a = b + c