Measures of Location Topic Review summary

Key learning points

• Mean $\\bar x=\\frac{\\sum x}{n}$ or $\\frac{\\sum f x}{\\sum f}$.
• Median: middle value (or interpolate in grouped data).
• Mode / modal class: most frequent value or tallest histogram bar.
• Coding $y=\\frac{x-a}{b}$ ⇒ $\\bar x=a+b\\bar y$.
• Outliers affect the mean more than the median.

Worked example 1 — Mean

Values 2,3,7. Mean?

Working

Sum/count.

Worked example 2 — Coding

If $y=x-10$ and $\\bar y=3$, find $\\bar x$.

Working

Reverse the coding.

Worked example 3 — Mean \\\\bar x=\\\\\\\sum x{n} or \\\\\\\s

Mean $\\\\bar x=\\\\frac{\\\\sum x}{n}$ or $\\\\frac{\\\\sum f x}{\\\\sum f}$.

Working

Attempt without notes, then check the answers PDF.

Worked example 4 — Median: middle value (or interpolate in gr

Apply this idea from the Topic Review: Median: middle value (or interpolate in grouped data).

Working

Attempt without notes, then check the answers PDF.

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.