Basic probability; Basic probability. ... There are two central rules of probability. The first is that probability is always positive. \[0\le \Pr{\left(A\right)}\le1\] ... Tree diagrams are helpful ...

Probability - Eduqas Tree diagrams Probabilities can be written as fractions, decimals or percentages on a scale from 0 to 1. Knowing basic facts about equally likely outcomes can help to solve ...