Data Interpretation • Topic 2 of 5

Bar Graphs

Each bar's height is a value; read it against the axis scale. Questions ask for totals across bars, the difference between two bars, percentage change from one year to the next, or which bar is largest/smallest. With grouped/stacked bars, identify the segment before computing.

✅ Solved examples

1. Production (in tonnes) over 2019-2022: 40, 50, 60, 50. Total?
40+50+60+50 = 200.
2. Percentage increase from 2019 (40) to 2021 (60)?
(60-40)/40 x 100 = 50%.
3. Average production over the four years?
200/4 = 50 tonnes.
4. By what percent did 2022 (50) fall from 2021 (60)?
(60-50)/60 x 100 = 16.67%.

✏️ Practice — try these, take hints as needed

1. Bars 30, 45, 25. Total?
Add.
—
—
100
2. Increase from 30 to 45?
15/30.
x 100.
—
50%
3. Average of 30, 45, 25?
100/3.
—
—
33.33
4. Difference between largest and smallest of 30,45,25?
45 - 25.
—
—
20
5. 25 is what percent of total 100?
25/100.
—
—
25%

📝 Topic test — 8 questions

Auto-graded with full solutions; saved to your dashboard. Use the calculator and formula sheet (top-right) any time.

Loading questions…
← Tables Pie Charts →