Interpreting Graphs

Graphs turn a table of numbers into a picture you can read at a glance.

• A bar graph shows each category as a bar; the taller the bar, the bigger the value. Always read the scale up the side.
• A pictograph uses a symbol to stand for a fixed number of items. Always read the key — one picture might mean $4$, or $10$, or $100$.

Worked example. In a pictograph where each $\bigstar = 10$ learners, a row of $4$ stars means $4 \times 10 = 40$ learners, and a row of $4\tfrac{1}{2}$ stars means $45$.

Once you can read single values, you can answer "how many more" (subtract) and "how many altogether" (add).