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S3 ICT: Algorithms and Flowcharts (Paper 3: challenge)
S3 ICT: Algorithms and Flowcharts (Paper 3: challenge)
S3 Geography population structure paper three, challenge: ten questions on percentage points versus per cent, effective ratios, compound growth of the elderly, offsetting changes in the structure, and the demographic dividend.
Direct answers Answers in order: 13.5 points and 30.0 per cent, 42.9 people, 75.0 per cent, 300 000 people, 113.3, about 108 057 people, 44.6 per cent, 42.9 and 24.0 per cent, it ignores participation and age mix, and a high working age share with a low ratio.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 20 |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: S3 Geography: Population Structure and Dependency Ratio |
| Level | S3 |
02 Questions (10 items)
- FoundationA dependency ratio rises from 45.0 to 58.5 per cent. Give the change in percentage points and the percentage increase.
- FoundationIn a place where the working age group is 70 per cent of the population, how many dependants does each 100 working age people support?
- FoundationA total dependency ratio of 40.0 splits into 30.0 for the elderly and 10.0 for children. What share comes from the elderly?
- IntermediateWith 500 000 people of working age and a participation rate of 60 per cent, what is the labour force?
- IntermediateIf dependants number 340 000 and the labour force is 300 000, what is the effective dependency ratio using the labour force as denominator?
- IntermediateAn elderly population of 60 000 grows four per cent a year. How many after fifteen years?
- ChallengeChildren fall from 90 000 to 72 000 and the elderly rise from 60 000 to 84 000 while 350 000 stay of working age. What is the new total dependency ratio?
- ChallengeIf the child group drops by 24 000 and the elderly rise by 24 000 with 350 000 still of working age, what are the total and old age ratios?
- ChallengeA student says a lower dependency ratio is always better. What does this overlook?
- Error redoWhat does the demographic dividend refer to?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 13.5 percentage points, which is a 30.0 per cent increase. | Subtract to get percentage points and divide by the original value for the percentage rise. |
| 2 | 42.9 people. | The remaining 30 per cent are dependants, so 30 divided by 70 gives 42.9. |
| 3 | 75.0 per cent. | 30 divided by 40 gives 75 per cent, showing the burden is mainly from the elderly. |
| 4 | 300 000 people. | The participation rate counts only those employed or seeking work, so the rest are outside the labour force. |
| 5 | 340 000 divided by 300 000, giving 113.3. | A ratio above 100 means each worker supports more than one dependant. |
| 6 | About 108 057 people. | 60 000 times 1.04 to the fifteenth power, well above a flat 2 400 a year. |
| 7 | (72 000 + 84 000) divided by 350 000, giving 44.6 per cent. | Children drop by 18 000 while the elderly add 24 000, a net rise of 6 000 dependants, so the ratio edges up. |
| 8 | The total ratio stays at 42.9 per cent while the old age ratio rises to 24.0 per cent. | One group falls as the other rises by the same amount, so the total is unchanged even though the structure ages. |
| 9 | It overlooks the participation rate and the age mix of the dependants. | A low ratio with a very low participation rate can still mean heavy real pressure. |
| 10 | A period when the working age share is high and the dependency ratio is low. | Savings and productivity are higher then, but the dividend fades as the population ages. |
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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