Pictograms (AQA GCSE Maths): Revision Notes
Pictograms
What is a pictogram?
A pictogram is a visual method of displaying data using pictures or symbols to represent information. You can create pictograms from data collected in surveys, tally charts, or frequency tables. They make it easy to see and compare different amounts of data at a glance.
Pictograms are particularly useful for presenting statistical data to audiences who may find traditional charts or graphs difficult to interpret, as the visual symbols make the information more accessible and engaging.
Essential components of pictograms
The key
Every pictogram must have a key (also called a legend). This is the most important part because it tells you exactly what each symbol represents.
For example:
- One television symbol = 2 people
- One house symbol = £50,000
- One car symbol = 5 cars
Without a key, you cannot read or understand the pictogram correctly. Always look for the key first before attempting to interpret any pictogram data.
Reading the data
To find out how many items each row represents, you need to follow these essential steps:
- Look at the key first
- Count the symbols in the row
- Multiply the number of symbols by what each symbol represents
Working with partial symbols
Sometimes you'll see half or partial symbols in pictograms. These represent a fraction of the full amount.
For example, if one symbol = 4 items, then:
- Half a symbol = 2 items
- Quarter of a symbol = 1 item
When working with partial symbols, it's helpful to think of them as fractions. A half symbol is of the key value, a quarter symbol is of the key value, and so on.
Worked examples
Example 1: Films watched
Worked Example: Reading Film Data from a Pictogram
If a pictogram shows Adam watched films with a key stating one symbol = 4 films:
Step 1: Identify what each symbol represents
- 1 symbol = 4 films (from the key)
Step 2: Calculate for each month
- June: 2 symbols = films
- July: 1.5 symbols = films
- August: 1.25 symbols = films
Step 3: Find the total Total = films
Example 2: Creating pictograms
Worked Example: Drawing a Pictogram
When you need to draw a pictogram, follow these steps:
Step 1: Choose an appropriate symbol Step 2: Decide what each symbol will represent Step 3: Work out how many symbols you need for each category Step 4: Draw the symbols neatly in rows Step 5: Always include a clear key
Practical calculation: For 10 items with a key of 1 symbol = 4 items:
- You need symbols
- This equals 2 full symbols (8 items) + half a symbol (2 items) = 10 items total
Connection to tallies
Tallies work similarly to pictograms and provide another visual method for recording data. In tally marks:
- Four vertical lines with a diagonal line through them = 5
- This is like a pictogram where each group represents 5 items
Both tallies and pictograms use visual symbols to represent quantities of data, making them valuable tools for data collection and presentation.
The connection between tallies and pictograms shows how different visual representations can serve similar purposes in mathematics and statistics.
Exam tips
Critical Exam Success Strategies:
- Always check the key before answering any questions
- Be careful with partial symbols - work out exactly what fraction they represent
- When drawing pictograms, make your symbols clear and evenly spaced
- Double-check your calculations by adding up totals
- Show all your working steps clearly
Key Points to Remember:
- Every pictogram needs a key - this tells you what each symbol represents
- Count carefully - multiply the number of symbols by the key value
- Partial symbols matter - half a symbol means half the value
- Check your work - add up totals to verify your answers
- Draw neatly - when creating pictograms, make symbols clear and aligned