Reading charts and tables
Strategy card
Interpret data precisely and know what it can and can't support.
- Step 1: Identify variables, units and scale.
- Step 2: Extract the needed values exactly.
- Step 3: Compute rates, averages, or percent change carefully.
- Step 4: Ask whether the claim goes beyond what the data shows.
Tip: Percent change = (new − old) ÷ old. The base matters.
Worked example
What is the mean (average)?
| Mon | Tue | Wed | Thu | Fri | |
|---|---|---|---|---|---|
| cups | 100 | 105 | 110 | 35 | 30 |
- A: 76 (the answer)
- B: 78
- C: 77
- D: 73
- E: 70
Why: Total 100 + 105 + 110 + 35 + 30 = 380. Divide by 5: 380 ÷ 5 = 76.
Your turn
Your turn 1 of 3
What is the range (largest minus smallest)?
| Fish | Hamster | Turtle | Rabbit | |
|---|---|---|---|---|
| votes | 10 | 55 | 40 | 15 |
Your turn 2 of 3
What is the range (largest minus smallest)?
| 2021 | 2022 | 2023 | 2024 | 2025 | |
|---|---|---|---|---|---|
| hundred visitors | 75 | 25 | 45 | 100 | 70 |
Your turn 3 of 3
What is the mean (average)?
Keep practicing
Grown-ups: Talk about correlation vs. cause in a real article. Parent guide
Next lesson: Unknowns and balances