Different Strategies (Leaving Cert Mathematics): Quizzes

For small sample spaces

$12$

Arrangements of $n$ distinct objects

$24$

Order matters vs doesn't matter

$\frac{n!}{(n-r)!}$

$\frac{n!}{r!(n-r)!}$

For multiple overlapping groups

$30$

$120$

Fundamental Principle of Counting