Key Idea: Topic 6.7 covers the use of descriptive statistics in business decision-making, including measures of central tendency (mean, median, mode) and measures of dispersion (range, standard deviation). Students learn to interpret statistical data and apply it to business contexts.
Key Exam Takeaways
- Mean = total ÷ number of values (affected by outliers)
- Median = middle value when ordered (not affected by outliers)
- Mode = most frequent value (useful for popularity)
- Choose the right measure for the data — outliers matter!
- Always show your working in calculations
- Range = highest − lowest (simple but limited)
- Standard deviation = average distance from the mean (more reliable)
- Low dispersion = consistent, predictable. High dispersion = variable, risky
- Businesses prefer low dispersion in sales and quality
- You interpret SD in exams — you don't calculate it
- Statistics help identify trends, compare performance, forecast and spot problems
- Mean, median, mode, range and SD are all useful for different situations
- You must be able to CONSTRUCT bar charts (simple + stacked) and pie charts
- Bar charts: labelled axes, to scale, equal width bars, key if needed
- Pie charts: calculate degrees (value divided by total x 360), label segments, use protractor