Maths | Year 5 | Statistics | Line Graphs | Lesson 1 of 5: Hot Drinks Line Graphs

MathsStatistics

Hot Drinks Line Graphs

Success Criteria

Aim

• I can identify the features of a line graph.

• I can interpret data in tables and line graphs.

• I can answer comparison, sum and difference questions about data presented in a line graph.

• I can answer questions about data presented in a line graph.

In their science lesson, Class 5 are investigating howthe temperature of boiled water changes over time.

Temperature Investigation

Time in Minutes

Temperature in °C

Complete the table showing the results of Class 5’s science investigation.

Temperature Investigation

0 100

5

10

15

20

50

30

25

20

Time in Minutes

Temperature in °C

0 100

5 50

10 30

15 25

20 20

The children from Class 5 wrote four questions about their data.Can you answer them?

Temperature Investigation

By how many degreesdid the water cool over the

twenty minutes?

80°C

By how many degreesdid the water cool overthe first five minutes?

50°C

By how many degreesdid the water cool from the fifth minute to the tenth

minute?

20°C

By how many degreesdid the water cool fromthe tenth minute to the

fifteenth minute?

5°C

Class 5 repeat their investigation, but this time they recordthe change in temperature of a cup of coffee over 20 minutes.

Temperature over Time

Time in Minutes

Temperature in °C

0 84

5 40

10 27

15 23

20 21

Class 5’s teacher, Mrs Chambers, explains to her classthat they can draw a line graph of the data.

Line Graphs

Time in Minutes

Temperature in °C

0 845 4010 2715 2320 21

Line graphs areused to show changes

to a measurementover time.

In this investigation,we have measured how

the temperature changed every five minutes.

A line graph has a horizontal axis.In this investigation, the horizontal axis is showing time in minutes.

Line GraphsA line graph also has a vertical axis.

In this investigation, the vertical axis is showing temperature in °C.Data is plotted on to a line graph in the same way as a coordinate grid.

These data plots are then joined with straight lines.The line shows us visually how the temperature of the coffee changed.We can see that the temperature of the coffee dropped morequickly at the start of the twenty minutes than at the end.

A Line Graph to Show the Change in Temperature of a Cup of Coffee

Time in Minutes0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 1920

85

Tem

per

atu

re in °

C

45

20

50

40

3035

25

55606570

8075

Using the line graph, we can get approximate temperatures of the coffeeat any time over the 20 minutes, not just at five minute intervals.

A line graph can also be used to give usdata between the plotted measurements.

Line Graph QuestionsWhat was the temperature of the coffee at minute 7 of the investigation? What was the temperature of the coffee at minute 4 of the investigation?

At which minute of the investigation wasthe temperature of the coffee 32°C?

During which minute of the investigation wasthe temperature of the coffee 60°C?

A Line Graph to Show the Change in Temperature of a Cup of Coffee

Time in Minutes0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 1920

85

Tem

per

atu

re in °

C

45

20

50

40

3035

25

55606570

8075

Line Graph ChallengeFinally, Mrs Chambers shows the children a line graph whichshows the change in temperature of two different hot drinks.

A Line Graph to Show the Change in Temperature of a Cup of Coffee and a Cup of Lemon Tea

Time in Minutes0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

85

Tem

per

atu

re in °

C

45

20

50

40

3035

25

55606570

8075

9590

100Key/Legend

= Coffee= Lemon Tea

16

A line graph that shows two sets of data can be used for comparison.A key will show you which line represents which data.Which drink had a higher temperature at minute 3?What was the difference in temperature of the two hot drinks at minute 3?

Hot Drinks Line GraphsUse your marvellous maths skills to complete these activity sheets:

Dive in by completing your own activity!

Diving into Mastery

Soup Temperature RevealChoose a question to answer about the line graph. Click on the box

once to check your answer and then again to reveal a part of the picture!

Success Criteria

Aim

• I can identify the features of a line graph.

• I can interpret data in tables and line graphs.

• I can answer comparison, sum and difference questions about data presented in a line graph.

• I can answer questions about data presented in a line graph.