大象传媒

We introduce pie charts, explaining first that they show relative proportions. Examples demonstrate the usefulness of pie charts; we have an intuitive visual understanding of simple fractions and proportions and pie charts exploit this. Numerically, we show the connection between fractions, decimals, percentages and the angles in a pie chart. We also point out that the angle of a sector should not be confused with either the actual amount represented or the percentage represented by that sector. We see examples of calculations that can be done from a given pie chart. End sketch demonstrates calculating a fraction of a fraction.