year 8 maths

9C
Line graphs
543
9 The temperature in a lounge room is measured frequently throughout a particular day. The results
are presented in a line graph, as shown. The individual points are not indicated on this graph to
reduce clutter.
a
Temperature (°C)
Twice during the day the heating was switched on. At what times do you think this happened?
Explain your reasoning.
b When was the heating switched off? Explain your reasoning.
c The house has a single occupant, who works during the day. Describe when you think that
person is:
i waking up
ii going to work
iii coming home
iv going to bed
d These temperatures were recorded during a cold winter month. Draw a graph that shows what
the lounge room temperature might look like during a hot summer month. Assume that the
room has an air conditioner, which the person is happy to use when at home.
10 Draw travel graphs to illustrate the following journeys.
a A car travels:
• 120 km in the first two hours
• 0 km in the third hour
• 60 km in the fourth hour
• 120 km in the fifth hour
b A jogger runs:
• 12 km in the first hour
• 6 km in the second hour
• 0 km in the third hour
• at a rate of 6 km per hour for two hours
30
20
10
0
Temperature in a lounge room
6 a.m.
8 a.m.
10 a.m.
12 p.m.
2 p.m.
4 p.m.
Time
6 p.m.
8 p.m.
10 p.m.
12 a.m.
Cambridge Maths NSW
Stage 4 Year 8 Second edition
ISBN 978-1-108-46627-1 © Palmer et al. 2018
Cambridge University Press
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