StatisticsKey Facts

Key Facts About Measures of Spread

Part of Range & IQRGCSE Mathematics

This key facts covers Key Facts About Measures of Spread within Range & IQR for GCSE Mathematics. Revise Range & IQR in Statistics for GCSE Mathematics with 12 exam-style questions and 20 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 2 of 7 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 2 of 7

Practice

12 questions

Recall

20 flashcards

Key Facts About Measures of Spread

  • Range: Highest value - Lowest value
  • Quartiles: Values that divide ordered data into four equal parts
  • Q1 (Lower Quartile): 25% of data is below this value
  • Q2 (Median): 50% of data is below this value
  • Q3 (Upper Quartile): 75% of data is below this value
  • IQR (Interquartile Range): Q3 - Q1 (middle 50% spread)

Keep building this topic

Read this section alongside the surrounding pages in Range & IQR. That gives you the full topic sequence instead of a single isolated revision point.

Practice Questions for Range & IQR

The range of a set of data is calculated by:

  • A. Adding all the values together
  • B. Dividing the total by the number of values
  • C. Subtracting the smallest value from the largest value
  • D. Finding the middle value when ordered
1 markfoundation

Explain why the interquartile range (IQR) is sometimes preferred over the range as a measure of spread.

2 marksstandard

Quick Recall Flashcards

What are quartiles?
Quartiles are values that divide an ordered dataset into four equal parts: - Q1 (Lower quartile): 25% below - Q2 (Median): 50% below - Q3 (Upper quartile): 75% below
What is the range?
The range is the difference between the highest value and the lowest value in a dataset. Range = Highest value - Lowest value

Want to test your knowledge?

PrepWise has 12 exam-style questions and 20 flashcards for Range & IQR — with adaptive difficulty and instant feedback.

Join Alpha