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S3 ICT: Algorithms and Flowcharts (Paper 1: basics)
S3 ICT: Algorithms and Flowcharts (Paper 1: basics)
S3 Geography population structure paper one, basics: ten questions on the three dependency ratio formulas, reading pyramid bases and bell shapes, and working backwards from a ratio.
Direct answers Answers in order: 42.9 per cent, 25.7 per cent, 17.1 per cent, a high birth rate with many children, 49.7 per cent, the 15 to 64 working age group, 300 000 people, sixty people, the stationary type, and a large child group also raises the ratio.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 20 |
| Difficulty mix | Foundation 3 · Challenge 3 · Intermediate 3 · Error redo 1 |
| Chapter | Chapter: S3 Geography: Population Structure and Dependency Ratio |
| Level | S3 |
02 Questions (10 items)
- FoundationA place has 500 000 people, with 90 000 aged 0 to 14, 350 000 aged 15 to 64 and 60 000 aged 65 or over. What is the total dependency ratio?
- FoundationWith the same figures, what is the child dependency ratio?
- FoundationWith the same figures, what is the old age dependency ratio?
- ChallengeWhat does a wide base on a population pyramid normally show?
- IntermediateIf the elderly rise to 84 000 while the working age and child groups stay the same, what is the new total dependency ratio?
- IntermediateWhich age group forms the denominator of the dependency ratio, and why?
- IntermediateA place has 800 000 people and a dependency ratio of 60 per cent. How many dependants are there?
- ChallengeIn the same place, how many dependants does each 100 people of working age support?
- ChallengeA population pyramid with a bell shape, where the base and middle are similar in width, belongs to which type?
- Error redoA student claims that a higher dependency ratio always means more elderly people. Is this correct?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | (90 000 + 60 000) divided by 350 000, giving 42.9 per cent. | The dependent group combines the 0 to 14 and 65 plus groups, and the denominator is the working age group. |
| 2 | 90 000 divided by 350 000, giving 25.7 per cent. | Only the 0 to 14 group goes in the numerator and the denominator stays at the working age group. |
| 3 | 60 000 divided by 350 000, giving 17.1 per cent. | The old age ratio counts only the 65 plus group and is calculated separately from the child ratio. |
| 4 | A high birth rate and a large share of children. | The base is the youngest cohort, so a wide base means many people in that group. |
| 5 | (90 000 + 84 000) divided by 350 000, giving 49.7 per cent. | The numerator grows by 24 000 with an unchanged denominator, so the ratio moves from 42.9 to 49.7 per cent. |
| 6 | The 15 to 64 working age group, because this group is assumed to support the other two. | Putting dependants in the denominator would destroy comparability, so convention uses the working age group. |
| 7 | 300 000 people. | A ratio of 60 per cent means 500 000 people of working age, leaving 300 000 dependants. |
| 8 | Sixty people. | The ratio is already defined per hundred working age people, so the figure reads straight off as sixty. |
| 9 | The stationary type. | Each cohort is of similar size because both birth and death rates are low and steady. |
| 10 | No. A large child population also pushes up the total ratio. | The total ratio counts both children and the elderly, so the two parts must be read separately to judge ageing. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
An algorithm is a finite and unambiguous list of steps; flowcharts use a diamond for decisions and a parallelogram for input or output, combined through sequence, selection and iteration.Tutor Registration →
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