Data Handling
Focused last-minute revision with key concepts, formulas, worked examples, exam traps and practice.
Chapter Snapshot
- A full pie chart represents 360° and 100%.
- Sector angle = category/total × 360°.
- Probability lies between 0 and 1.
- Probability 0 means impossible and 1 means certain.
- For equally likely outcomes, probability = favourable outcomes / total outcomes.
What You Will Learn
- Read tables and graphs accurately
- Convert data into pie-chart angles
- Read values from pie charts
- Understand probability as likelihood
- Calculate simple probabilities
Last-Minute Chapter Map
Use this chapter in three passes:
- Understand the core ideas.
- Memorise formulas and exam traps.
- Attempt the compact practice set without looking at the answers.
Organising data
Tables and graphs make comparisons easier. Always read the graph title, axis labels, units and scale before extracting information.
Pie charts
A pie chart divides a circle into sectors. Each sector is proportional to that category's share of the total. Convert a category value to an angle by multiplying its fraction by 360°.
Reading sectors
To recover a category from a sector, divide the sector angle by 360° and multiply by the total value.
Probability
Probability measures chance. For equally likely outcomes, count favourable outcomes and divide by the total number of outcomes. Probability cannot be less than 0 or greater than 1.
Sector size represents each category's share of the total.
Formula Sheet
Formula / Key Relations
Pie-chart sector angle
Use the total of all categories.
Probability
Use only when outcomes are equally likely.
Probability range
0 impossible, 1 certain.
Worked Examples
Football occupies one quarter of the circle.
Favourable outcomes are 2, 4 and 6.
Exam Traps
Quick Revision
Quick Revision
- A full pie chart represents 360° and 100%.
- Sector angle = category/total × 360°.
- Probability lies between 0 and 1.
- Probability 0 means impossible and 1 means certain.
- For equally likely outcomes, probability = favourable outcomes / total outcomes.
- Revise the formula sheet once more before attempting questions.
Compact Practice
25% of a pie chart equals what angle?
View Solution
90°
Probability of an impossible event?
View Solution
0
Probability of getting a head on a fair coin?
View Solution
1/2
A 72° sector is what percent of a circle?
View Solution
20%
Final Chapter Summary
Chapter Summary
- A full pie chart represents 360° and 100%.
- Sector angle = category/total × 360°.
- Probability lies between 0 and 1.
- Probability 0 means impossible and 1 means certain.
- For equally likely outcomes, probability = favourable outcomes / total outcomes.
- Prioritise correct method, clean working and final units where applicable.