This diagram covers Cumulative Frequency for Median within Grouped Data for GCSE Mathematics. Revise Grouped Data in Statistics for GCSE Mathematics with 14 exam-style questions and 20 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 7 of 8 in this topic. Focus on the labels, the relationships between parts, and the explanation that turns the diagram into an exam-ready answer.
Cumulative Frequency for Median
| Height (cm) | Frequency | Cumulative Frequency |
|---|---|---|
| 150 ≤ h < 160 | 5 | 5 |
| 160 ≤ h < 170 | 12 | 17 |
| 170 ≤ h < 180 | 15 | 32 |
| 180 ≤ h < 190 | 8 | 40 |
| 190 ≤ h < 200 | 3 | 43 |
Median position = (43 + 1) ÷ 2 = 22nd value
The 22nd value is in the 170 ≤ h < 180 class (highlighted)
Practice questions for Grouped Data
A frequency table uses the class intervals shown below. | Speed, s (mph) | Frequency | |---|---| | 0 < s ≤ 20 | 4 | | 20 < s ≤ 40 | 11 | | 40 < s ≤ 60 | 9 | | 60 < s ≤ 80 | 2 | A car travels at exactly 40 mph. Which class interval does this value belong to?
A teacher groups 30 students' test scores into four class intervals and calculates the estimated mean and estimated median. Explain why both the estimated mean and the estimated median from grouped data are only approximations of the true values. In your answer, refer to the assumptions made.