Year 5 Maths: Line Graph

What is a Line Graph?

A line graph is a way to show information using lines. It helps us see how things change over time or compare different things. In a line graph, we usually have two axes:

• The horizontal axis (or x-axis) runs from left to right.
• The vertical axis (or y-axis) runs from top to bottom.

Parts of a Line Graph

1. Title: This tells us what the graph is about.
2. Axes: These are the lines we just talked about. Each axis represents one part of the information.
3. Points: These are dots on the graph that show values.
4. Line: The dots are connected by lines to show how the values change.

How to Read a Line Graph

1. Look at the title to understand what the graph is showing.
2. Check the axes to see what each one represents. The x-axis often shows time (like days or months), and the y-axis shows the quantity (like temperature or sales).
3. Find the points plotted on the graph. Each point shows a value at a certain time.
4. Follow the lines to see how the values change. If the line goes up, it means the value is increasing. If it goes down, the value is decreasing.

Example of a Line Graph

Imagine we have a line graph showing the temperature in degrees Celsius over five days:

• Day 1: 15°C
• Day 2: 17°C
• Day 3: 20°C
• Day 4: 18°C
• Day 5: 21°C

The graph would look like this:

• On Day 1, you put a point at 15 on the y-axis.
• On Day 2, you put a point at 17.
• You keep doing this until Day 5.
• Then, you connect the points with a line.

Key Rules for Creating a Line Graph

1. Always label your axes so everyone knows what they mean.
2. Use equal spacing between the points on the x-axis.
3. Make sure the scale on the y-axis fits your data. For example, if your highest number is 25, don’t go up to 100.
4. Connect your points with straight lines.

Tips and Tricks

• Practice: The more you draw and read line graphs, the easier it becomes.
• Use a ruler: This helps you draw straight lines and keep your points neat.
• Check your work: Make sure every point corresponds to the right value.

Questions

Easy Level Questions

1. What is a line graph?
2. Name the two axes of a line graph.
3. What does the title of a line graph tell us?
4. If a line goes up, what does that mean?
5. If a line goes down, what does that mean?
6. What do the dots on a line graph represent?
7. How do you connect the points on a line graph?
8. Why is it important to label your axes?
9. What are the two main pieces of information shown on a line graph?
10. Can you name a real-life example where you might use a line graph?
11. What do you need to make a line graph?
12. If the temperature increased from 10°C to 15°C, what would the line do?
13. How many points do you need to draw a line graph?
14. What does it mean if there are no points on a line graph?
15. If Day 1 is at 5°C and Day 2 is at 10°C, how will you show this on the graph?
16. What happens if you put a point at the wrong place?
17. Why should you use equal spacing on the x-axis?
18. What is the first step in drawing a line graph?
19. How can you tell which day is hotter on the graph?
20. If a graph shows sales increasing each month, what shape will the line have?

Medium Level Questions

1. How do you determine the scale for the y-axis?
2. If a line graph shows a temperature of 25°C on Day 3 and 15°C on Day 4, what can you say about the temperature drop?
3. If the line is flat, what does that mean about the values?
4. Why might a line graph be better than a bar chart for showing changes over time?
5. How would you plot a point at 12 on the x-axis and 20 on the y-axis?
6. What does it mean if a line graph has multiple lines?
7. If a point is missing from the graph, how might that affect the information?
8. How can you tell the highest value on a line graph?
9. If the y-axis goes up to 50, how would you label it?
10. Why is it important to have a clear title for your graph?
11. How do you show a decrease in sales over three months on a line graph?
12. What will happen if you connect the points incorrectly?
13. If a line graph represents the number of books read over six months, how would you plot that?
14. What patterns can you look for in a line graph?
15. How can you describe the trend if the line goes up and down?
16. How do you know if the data is accurate on the graph?
17. Can you use a line graph to show your favourite colours? Why or why not?
18. If Day 5 shows a temperature of 18°C, how do you represent this on the graph?
19. What do dashed lines in a line graph usually represent?
20. How would you explain a sudden spike in a line graph?

Hard Level Questions

1. What are some possible reasons for a sudden drop in a line graph?
2. If a line graph shows a steady increase, what does this suggest about the situation?
3. How can you use a line graph to predict future values?
4. If two lines cross on a graph, what does that indicate?
5. What would you do if your data points are not fitting nicely on the graph?
6. How can you compare two different sets of data on the same line graph?
7. What is the difference between a line graph and a scatter plot?
8. If you were to create a line graph for a yearly temperature change, what time frame would you use?
9. How do you determine the best title for your line graph?
10. What information is lost when a line graph has a very narrow scale?
11. If a line graph’s points are all clustered together, what does that indicate?
12. Explain how you would use a line graph to show your weekly exercise routine.
13. If you had to represent two data sets with different ranges on a single graph, how would you do it?
14. What does a point above the line in a line graph indicate?
15. How might a line graph change if new data is added?
16. If a line graph shows consistent growth, what conclusions can you draw?
17. How do you handle outliers when drawing a line graph?
18. If a line graph has a curve instead of a straight line, what does that suggest about the data?
19. How do you explain a graph with an unusual shape to someone who doesn’t understand it?
20. Why might you choose to use a line graph instead of a pie chart for certain data?

Answers

Easy Level Answers

1. A way to show information using lines.
2. Horizontal and vertical axes.
3. It tells us what the graph is about.
4. The value is increasing.
5. The value is decreasing.
6. They show values at certain times.
7. By drawing straight lines between them.
8. So everyone knows what they mean.
9. Time and quantity.
10. Tracking temperature or sales over time.
11. Data points and a scale.
12. The line will go up.
13. At least two points.
14. It means there’s no data to show.
15. You would plot a point at (1, 5) and (2, 10).
16. The graph will be inaccurate.
17. To ensure accurate representation of time.
18. You start by deciding the title and axes.
19. You look at the highest point on the y-axis.
20. The line will go up or down.

Medium Level Answers

1. You look at your highest and lowest values.
2. It means there was a 10°C drop.
3. It means the values are the same.
4. Because it shows change over time.
5. You find the point at (12, 20).
6. It means comparing different data sets.
7. It could make understanding the data harder.
8. By looking at the topmost point.
9. You label it with a clear range.
10. To help understand the data quickly.
11. By drawing a downward slope.
12. You would lose accuracy.
13. You find the values for each month and plot them.
14. You can look for trends or patterns.
15. You can describe how it rises and falls.
16. By checking against your original data.
17. No, it’s not a good fit for that data.
18. You would plot it at (5, 18).
19. They often represent estimated values.
20. It shows changes in data.

Hard Level Answers

1. Changes in conditions or data errors.
2. It suggests a positive trend.
3. By extending the line into the future.
4. It indicates where one value equals another.
5. Adjust the scale or change the graph type.
6. Use different colours or styles for the lines.
7. A scatter plot shows individual points without connection.
8. A full year, like January to December.
9. It should be specific to the data shown.
10. It can make the data look less significant.
11. It shows data is very similar.
12. You would plot sessions and duration.
13. Use different scales or two graphs.
14. It indicates an unexpected value.
15. It could change the shape of the graph.
16. It suggests stability in the data.
17. You can either adjust the scale or note it separately.
18. It indicates varying rates of change.
19. You would break down the data and explain each part.
20. It’s important to show the right type for the data