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S1 Maths: Ratio and Proportion (Paper 4 (error clinic))
S1 Maths: Ratio and Proportion (Paper 4 (error clinic))
Paper 4 (error clinic): ten questions on ratio and proportion with answers and one-line notes.
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: S1 Maths: Ratio and Proportion |
| Level | S1 |
02 Questions (10 items)
- FoundationSimplify the ratio 8 : 12.
- FoundationDivide 18 sweets in the ratio 2 : 7.
- FoundationFive identical notebooks cost $60. What do 9 cost at the same unit price?
- IntermediateGiven 6 : 5 = 42 : x, find x.
- IntermediateJuice and water are in the ratio 2 : 3 with 500 mL in total. Find the amount of water.
- IntermediateOn a 1 : 400 map, how long is a real distance of 24 m in cm?
- ChallengeTwo numbers are in the ratio 7 : 4 and differ by 27. Find them.
- ChallengeSimplify the ratio 45 : 60.
- ChallengeDivide 120 in the ratio 3 : 4 : 5.
- Error redoError clinic: a student simplified 6 : 9 to 3 : 2. What is correct?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 8 : 12 = 2 : 3. | Divide both terms by their highest common factor 4. |
| 2 | A gets 4 and B gets 14. | Nine parts make 18 sweets, so each part is 2. |
| 3 | Nine notebooks cost $108. | The unit price is $12. |
| 4 | x = 35. | Multiply both terms by 7. |
| 5 | Water is 300 mL. | Five parts of 100 mL each; water takes three parts. |
| 6 | It should be drawn 6 cm long. | Convert to cm first, then divide by 400. |
| 7 | The numbers are 63 and 36. | The difference of 3 parts equals 27, so one part is 9. |
| 8 | 45 : 60 = 3 : 4. | Divide both terms by 15. |
| 9 | The parts are 30, 40 and 50. | Twelve parts of 10 each. |
| 10 | The correct answer is 2 : 3; the terms were reversed. | Divide both terms by 3 and keep the order, or the value inverts. |
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.
In ratio questions the first step is always to make the parts match: divide by the highest common factor, or make the middle term of a linked ratio the same. To divide a quantity in a ratio, find the total number of parts, then the value of one part, then multiply back. A map scale is given in centimetres, so convert units before scaling. Rates such as speed and unit price are ratios of two quantities, and an average speed uses total distance over total time. Worker-days and speed-time pairs are inverse relations, so invert the ratio.Tutor Registration →
Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.
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