Probability

Probability

1. always between 0 and 1

   • probability= number of ways for something to happen/ total nuber of possible results
     • only works if all possible results are equally as likely
   • always add up to 1
     • p(event happens) + p(event doesnt happen)

2. estimating frequency

   • estimated times outcome will happen= probavility X number of trials
   • relative frequency= frequency/ no. of times you tried the experiment

3. tree diagrams

   • multiply along tree

4. for 'atleast' questions use 1- probability of less than many