Statistics and Charts
Simple steps, clear visuals, and full worked solutions. Take your time and check each label carefully.
Your progress
Level 10 / 100 XP
Introduction to Data
Data is information we collect to answer a question. In school, data helps us compare ideas fairly.
Simple idea
- Ask a question (example: What fruit do students like?)
- Collect answers
- Organise the results in a table or chart
Real-life examples
- How many minutes you read each day
- Rainfall each week
- How many goals a team scores each match
Worked example
Question: How many students read 2 books?
Working: The number 2 appears twice in the list.
Answer: 2 students.
Practice
How many students read 3 books?
Bar Charts
Bar charts compare categories. Bars must have equal width and clear labels.
- Read the title first
- Check the y-axis scale
- Compare bar heights
Chart summary: Football 9, Basketball 7, Swimming 5, Tennis 4.
Worked solutions
- Most popular sport: Football (9)
- How many chose Tennis? 4
- Difference between Football and Swimming: 9 − 5 = 4
- Total votes: 9 + 7 + 5 + 4 = 25
Practice
How many more students chose Football than Tennis?
Pictograms
Pictograms use symbols. Always read the key before answering.
Apples: ⭐⭐⭐
Bananas: ⭐⭐
Grapes: ⭐⭐⭐⭐
Worked solutions
Apples: 3 × 2 = 6
Bananas: 2 × 2 = 4
Grapes: 4 × 2 = 8
Total: 6 + 4 + 8 = 18
Practice
How many students chose apples and bananas together?
Pie Charts
Pie charts show parts of a whole circle. The whole circle is always 360°.
Chart summary: Reading 50%, Sport 30%, Gaming 20%.
Dataset and full working
Reading = 10, Sport = 6, Gaming = 4. Total = 20
- Reading: (10/20) × 360 = 180°, which is 50%
- Sport: (6/20) × 360 = 108°, which is 30%
- Gaming: (4/20) × 360 = 72°, which is 20%
Practice
What is the angle for Sport?
Line Graphs
Line graphs show how values change over time, like temperature, sales, or steps per day.
Chart summary: Mon 10°C, Tue 12°C, Wed 13°C, Thu 14°C, Fri 11°C.
Worked solutions
- Highest temperature: Thursday at 14°C
- Increase Monday to Thursday: 14 - 10 = 4°C
- Decrease Thursday to Friday: 14 - 11 = 3°C
Practice
How much did the temperature drop from Thursday to Friday?
Averages
Averages describe the centre of data. They help us summarise many values quickly.
Rules
Mean = total ÷ number of values
Median = middle value in ordered list
Mode = most common value
Range = highest - lowest
Full example (2,3,3,5,7)
Mean: (2+3+3+5+7) ÷ 5 = 20 ÷ 5 = 4
Median: middle value is 3
Mode: most frequent is 3
Range: 7 - 2 = 5
Practice
What is the range of 2, 3, 3, 5, 7?
Mixed Practice
Try these without peeking. Then check your working in the answers section.
- Total votes in the bar chart?
- How many people chose grapes in the pictogram?
- What percentage is Gaming in the pie chart dataset?
- What is the mean of 2, 3, 3, 5, 7?
Interactive mixed question
What is the mean of 2, 3, 3, 5, 7?
Answers Solution
- Total votes: 9 + 7 + 5 + 4 = 25
- Grapes in pictogram: 4 × 2 = 8
- Gaming percentage: (4 ÷ 20) × 100 = 20%
- Mean of 2, 3, 3, 5, 7: 20 ÷ 5 = 4
Tip: If stuck, ask: “What is the total?” and “What operation should I use?”