Page 190 - Mathematics Coursebook

19.3 Drawing conclusions

4 Zalika sees these bar line graphs in a magazine. They show the average monthly temperatures in
Cairo and Harare in January, April, July and October. Average monthly temperature in Harare
Average monthly temperature in Cairo
Average temperature (°C) 24 Average temperature (°C) 21
24
28
18
20
15
16
12
12
9
8
6
4
0
January
April
Month July October 3 0 January April July October
Month
a Is Zalika correct? Explain your answer.
I can tell it’s warmer in Harare in October than
it is in Cairo because the October line is longer.

b During which month is the temperature in Cairo double the temperature in Harare?
5 The pie charts show how Akila and Medina spend their money each week.

Akila Madina
Housing
Travel
Food
Other

a Medina says: ‘I spend a larger proportion of my money on housing, as the housing sector of my
pie chart is bigger than Akila’s.’
Is Medina correct? Explain your answer.
b Akila says; ‘I pay half the amount that Medina does on travel, as the angle of my travel sector is
half the size of the angle of Medina’s travel sector.’
Is Akila correct? Explain your answer.

Summary

You should now know that: You should be able to:
+ A pictogram uses pictures to represent data. + Draw and interpret
+ A bar chart uses bars to show data. – pictograms
– bar charts
+ A bar-line graph is similar to a bar chart, but the – bar-line graphs
bars are replaced with thick lines. – frequency diagrams
+ A frequency diagram is the same as a bar chart – pie charts.
except that the data has been grouped.
+ Draw conclusions based on the shape of graphs
+ A pie chart is a way of displaying data to show and simple statistics.
how an amount is divided or shared. + Work logically and draw simple conclusions.

+ You can use pictograms, bar charts, bar-line + Record and explain methods results and
graphs, frequency diagrams and pie charts to conclusions.
compare two sets of data.

+ Discuss and communicate findings effectively.
19 Interpreting and discussing results 189