Topic summary · IGCSE handout
Averages summary
Mean, median, mode and range summarise a data set in different ways. Know which average is appropriate and how outliers shift the mean.
Files: 7_averages_handout.pdf · 7_averages_handout_answers.pdf · free public downloads · diagrams in the PDFs
Key learning points
- Mean = total ÷ count; median = middle value once ordered; mode = most frequent.
- Range = largest − smallest (a measure of spread, not an average).
- For an even count, median is the mean of the two central values.
Worked example 1 — Mean and median
Data . Mean and median?
Working
Mean = total÷n; median = middle.
Worked example 2 — Mode
Data . Mode?
Working
Most frequent.
Worked example 3 — Mean from frequency
Values 1,2,3 with frequencies 2,3,5. Mean?
Working
Σ(value×freq)/Σfreq.
Scaffolded Learning Sheet and answers (PDFs)
This page is a short, searchable overview for revision and search engines. Use the Scaffolded Learning Sheet first, then the Answers PDF for a full written solution. The printable PDFs remain the main classroom resource.