Look at the following graph. What do you notice? What do you wonder? Write your inferences.

Step-by-step solution

Idea: This is a 100% stacked bar chart: each bar is all the disabled persons of one age group. Compare the same colour across bars to see how the mix changes with age, and remember it says nothing about how many people are in each group.

1. Notice: seeing disability grows from about 18% (0–19) to 25% (60+), and movement disability from about 13% to 25%: together half of disabled older people. Hearing stays around 18–20% in every group. Speech (≈ 9% → 4%), intellectual disability (≈ 8% → 2%) and ‘any other’ (≈ 21% → 11%) shrink with age. Multiple disability is highest for the 60+ group (≈ 12%) and next for 0–19 (≈ 9%).1 mark
2. Wonder: How many disabled persons are there in each age group? (A 100% chart cannot tell.) What is in ‘any other’? Why is multiple disability common in both the youngest and the oldest? Do the patterns differ between men and women, or villages and cities?1 mark
3. Inferences: disabilities linked to ageing (weak eyesight, joint and mobility problems) make up a larger part of disability among older people, while conditions present from birth or childhood (speech, intellectual) make up a larger part among the young. Help for older people should focus on vision and mobility; for the young, on speech and learning support. We cannot conclude that any group has more disabled persons in number.1 mark

Answer to write in the exam

Common mistakes that cost marks

• Saying older people have more movement disability in number. The chart shows shares within each age group, not counts.
• Reading the scale as numbers of people instead of percentages.
• Listing observations without any inference or question, which the question asks for.

How this can come in the exam

Try one yourself

A 100% bar shows that 30% of a town’s accidents in 2010 and 40% in 2020 involved two-wheelers. Can we say the number of two-wheeler accidents rose?

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  (ii) % of cows increased, % of sheep increased, % of chickens increased
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