S1 Revision/Notes – Pie Charts
Revision Notes on Pie Charts
I asked several people if they could swim.
Good news: 100 said they could.
Bad news: I asked 400 people.
Sometimes it is not the frequency which provides the important information. In
this case it is more important to see that only ¼ of those asked could swim.
Pie charts are useful for comparing categories. They can, however, be more
difficult to construct.
The angle at the centre of each sector is related to the frequency and allows us
to see how the frequencies are shared amongst the categories.
Please attempt the questions below at the appropriate level:
2nd Level Questions
1.
Other
Spain
America
UK
France
The pie chart shows the holiday destinations of pupils in Class 1G.
a. Which was the most popular destination?
b. Which was more popular, America or France?
c. What does ‘other’ mean?
2. A restaurant found that on a Saturday night,
¼ of meals ordered were vegetarian and
¾ were non-vegetarian.
Copy and complete the pie chart to illustrate this data. (Make your circle at
least 4 cm across.)
3. At a school, a pie chart was drawn up to show how many pupils were born in
each of the seasons.
Use the pie chart to find out how many of the 30 pupils were born in:
(a) Autumn
(b) Winter
(c) Summer
(d) Spring
3rd / 4th Level Questions
1. To create a pie chart, you need to be able to divide a circle into sectors.
a. How can you divide a circle into halves?
b. Draw five circles, at least 4 cm across. Divide one into halves, another into
quarters, the next into eighths, another into sixths and the last into thirds.
2. The favourite fruit of pupils in Class 1F is shown in this pie chart.
a. What fraction of pupils preferred grapes?
b. How many times more popular were bananas than apples?
c. How many times more popular were bananas than oranges?
3. This pie chart has been divided into 10 equal sections. Each bit stands for
1
10
(a) Write down the fraction belonging to each
newspaper.
(b)
400 people were asked their favourite
newspaper. How many people chose:
(i)
Record
(ii) Times
4. (a) 20% of the tracks on an album have a slow beat,
70% are fast and the rest are somewhere in-between.
Draw a pie chart using the template below to illustrate this information.
(b) In a collection of 60 albums, how many
would you expect to have:
(i) a slow beat
COPY
(ii) a fast beat.
5. The percentage of free time at lunchtime in Blackness Academy is 50% and
the percentage spent on eating is 25%. The rest is spent on queuing.
a. Draw a pie chart to illustrate this data.
b. Compare the time spent queuing with the time spent eating.
6. A survey of ice-cream sales from a van was made and the results are shown
on the pie chart.
The pie chart is divided into 8 sectors.
Each sector is one eighth of the whole pie.
If the survey represented 240 people, how many of the 240 chose :(a) lime
(b) strawberry
(c) vanilla
(d) chocolate?
7. This pie chart is divided into 20 equal sectors.
a. What percentage is represented by
i. A
ii. B
iii. C
iv. D
b. How many of the 20 sectors would represent 20%?
8. A survey on traffic passing through a roundabout from the east showed that
40% exited to the north, 25% left to the south and 35% went west.
a. Draw a pie chart using the template below to illustrate this data.
b. If 500 cars went through the
roundabout on the survey, how many of
them exited to the north?
9. On a trip to the cinema, Megan estimated that 15% of the cost went on bus
fares, 35% on refreshments, 10% on sweets and 40% on the entry fee.
Construct a pie chart using the same template above to illustrate the ‘cost of a
night at the movies’.
10. Over a year, John logged the state of a set of traffic lights as he arrived at
them. The pie chart illustrates his findings.
a. On a typical day, what colour are the lights most likely to be at?
b. He passed that set of lights 300 times that year. How often were the lights
i. red
ii. amber
iii. green?