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Topic summary · Foundation · CIE Core

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: foundation-8 Averages handout.pdf · foundation-8 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 2,3,7,8,102,3,7,8,10. Mean and median?

Working

xˉ=6, median=7\bar x=6,\ \text{median}=7

Mean = total÷n; median = middle.

Worked example 2 — Mode

Data 4,4,5,6,6,6,74,4,5,6,6,6,7. Mode?

Working

66

Most frequent.

Worked example 3 — Mean from frequency

Values 1,2,3 with frequencies 2,3,5. Mean?

Working

2.32.3

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.

Averages summary — worksheet & answers PDF