IGCSE Mathematics Extended E8.1.4 Understand that the probability of an event not occurring = 1 – the Question Bank

• Understand that the probability of an event not occurring = 1 – the probability of the event occurring. P(A) is the probability of A P(A′) is the probability of not A Probabilities should be given as a fraction, decimal or percentage. Problems may require using information from tables, graphs or Venn diagrams. e.g. P(B) = 0.8, find P(B′)