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Primary General Studies: Transport and Communication in Hong Kong (Paper 3 (challenge))
Primary General Studies: Transport and Communication in Hong Kong (Paper 3 (challenge))
Paper three adds multi step sums, time zones, emissions and fare combinations, so data must be sorted before choosing the steps.
Direct answers For multi step questions list each step with its unit before combining, so kilometres are never mixed with metres.
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: Primary General Studies: Transport and Communication in Hong Kong |
| Level | parts of a closed circuit, conductors against insulators, series against parallel, adding up battery voltage, and electrical safety |
02 Questions (10 items)
- FoundationA trip runs 1 hour at 90 km/h and then 1.5 hours at 60 km/h. What is the average speed for the whole trip?
- FoundationA bus travels at 15 m/s. What is that in km/h?
- FoundationEach ferry crossing takes 12 minutes and there are 9 crossings a day. How many hours is that?
- IntermediateThe first ferry leaves at 6:20 a.m., the crossing takes 38 minutes and the walk takes 7 minutes. When does the traveller arrive?
- IntermediateA bus emits 60 g of carbon dioxide per passenger kilometre and a car 150 g. What is the difference over 10 km?
- IntermediateIt is 9 p.m. in Hong Kong and London is 8 hours behind. What time is it in London?
- ChallengeAn email attachment limit is 20 MB and a 25 MB file must be sent. What is the fewest number of emails, and how large is each?
- ChallengeUsing 1.2 GB a day for 30 days, what is the total, and by how much does it exceed a 5 GB plan?
- ChallengeAn adult fare is $23.6 and a senior fare is $2.0. What do two adults and two seniors pay for two trips each?
- Error redoA classmate claims 72 km/h is faster than 20 m/s. Is that right?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 72 km/h. | The total distance is 180 km over 2.5 hours, so 180 divided by 2.5 is 72. |
| 2 | 54 km/h. | Multiply metres per second by 3.6, so 15 times 3.6 is 54. |
| 3 | 1.8 hours. | 12 times 9 is 108 minutes, which is 1.8 hours. |
| 4 | At 7:05 a.m. | 6:20 plus 38 minutes is 6:58, and 7 more minutes gives 7:05. |
| 5 | 900 g. | The gap is 90 g per kilometre, so 10 km gives 900 g per passenger. |
| 6 | 1 p.m. in London. | 21 minus 8 is 13, which is 1 p.m., so check which city is ahead. |
| 7 | Two emails of 12.5 MB each. | 25 divided by 2 is 12.5, which stays under the 20 MB limit. |
| 8 | 36 GB in total, which is 31 GB over the plan. | 1.2 times 30 is 36, and subtracting 5 leaves 31 GB over the limit. |
| 9 | $102.4 in total. | Adults give 23.6 times 2 times 2, which is 94.4, and seniors add 8. |
| 10 | No, the two speeds are equal. | 20 times 3.6 is 72, so 20 m/s is 72 km/h, and numbers in different units cannot be compared directly. |
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.
Paper four clears the conductor, insulator and battery direction misconceptions.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.