Pie Charts Flashcards

All 6 cards in this deck

What is the formula for the angle of a sector in a pie chart?

$\text{angle} = \dfrac{\text{frequency}}{\text{total frequency}} \times 360^\circ$

What are the steps to draw an accurate pie chart from a frequency table?
e.g. Tea 50, Coffee 30, Hot chocolate 10

1. Add the frequencies to get the total: $50+30+10=90$
2. Work out each angle as $\frac{\text{frequency}}{\text{total}}\times 360^\circ$: $200^\circ$, $120^\circ$, $40^\circ$
3. Draw the sectors with a protractor and label each with its category: Tea, Coffee, Hot chocolate

What quick method gives the angle per item in a pie chart?
e.g. a total frequency of 60

Divide $360^\circ$ by the total frequency, then multiply by each frequency.
$360\div 60 = 6^\circ$ for each item

What must be shown on a finished pie chart to gain the labelling mark?

Each sector labelled with its category name from the table, not just the angle size.

How do you find what fraction of the data a sector of a pie chart represents?
e.g. a sector of $90^\circ$

$\dfrac{\text{sector angle}}{360}$, simplified.
$\frac{90}{360}=\frac14$

True or false? The angles in a pie chart must add up to $360^\circ$.

True.
The whole circle represents the whole data set.