Building Up the Picture
📊 Building Up the Picture
Imagine you're organizing a charity run and need to know how many runners finish within certain times to plan medal ceremonies and refreshment stations. Rather than looking at each individual time, cumulative frequency helps you see the "running total" - how many runners have finished by each time checkpoint. This running total builds up step by step, giving you the complete picture of when to expect different numbers of finishers.
Mathematics glossary
- What is cumulative frequency?
- Cumulative frequency is the running total of frequencies up to and including each class. It shows how many data values fall below the upper boundary of each class.
Earn the mark scheme marks
💡 Exam Tips for Cumulative Frequency
Drawing Cumulative Frequency Curves:
- Use upper boundaries: Plot against the upper limit of each class interval
- Start at origin: First point is usually (lowest upper boundary, 0)
- Smooth curve: Draw a smooth curve through the points (not straight lines)
- Check totals: Final point should have y-coordinate equal to total frequency
- Appropriate scale: Use scales that show all data clearly
Reading Values:
- Horizontal then vertical: Always go horizontally to the curve, then vertically to the axis
- Estimate carefully: Read values as accurately as possible from the graph
- Show working: Draw the construction lines clearly on your graph
- Round sensibly: Round to appropriate precision (usually 1 decimal place)
Now try it yourself
Quiz · Question 1 of 14
Cumulative frequency is:
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This topic in real past papers
Every real exam question we've found on cumulative frequency, with a full worked answer.
AQA Paper 1
Three of the four sittings we have full papers for build a question around a cumulative frequency diagram, either constructing one from a frequency table or reading estimates from a given one.
Edexcel Paper 1
Two of the three sittings we have full papers for start from a grouped frequency table and ask for a statistic or a graph built from it.
Edexcel Paper 2
Two of the three sittings we have full papers for build a cumulative frequency graph from a table of data, and June 2019 also asks for an estimated percentage to be read from it.