## Modelling Categories of Disease and Sufferer With Matrices

Age\Severity | Slight | Mild | Severe |

0 - 30 | 0.5 | 0.3 | 0.2 |

30 - 60 | 0.4 | 0.3 | 0.3 |

60 - 90 | 0.1 | 0.4 | 0.5 |

We can represent the table by the mat ix

\[\left( \begin{array}{ccc} 0.5 & 0.3 & 0.2 \\ 0.4 & 0.3 & 0.3 \\ 0.1 & 0.4 & 0.5 \end{array} \right)\]

, the the people above by the vector \[\begin{pmatrix}300\\500\\200\end{pmatrix}\]

.\[\left( \begin{array}{ccc} 0.5 & 0.3 & 0.2 \\ 0.4 & 0.3 & 0.3 \\ 0.1 & 0.4 & 0.5 \end{array} \right)\begin{pmatrix}300\\500\\200\end{pmatrix}= \begin{pmatrix}370\\320\\310\end{pmatrix}\]

370 people have a slight form of the disease, 320 have a mild form of the disease, and 310 have a severe form of the disease.