Fundamental Principle of Counting (Leaving Cert Mathematics): Flashcards

Total no. of possible outcomes in a sequence of events

$m \times n$

$m_1 \times m_2 \times \ldots \times m_k$

Outcomes of one event don't affect outcomes of another

When listing all possibilities is impractical

Multiply the no. of ways each event can occur

$3 \times 2 = 6$ outfits

$6 \times 6 = 36$ outcomes

2 letters followed by 3 digits

$26 \times 26 \times 10 \times 10 \times 10 = 676,000$