This set practises the planning skills in 0653 revision and route planning.
All data is invented. Try each question first, then open the answer. Work from easier to harder.
Questions
1. Which qualification code is Cambridge IGCSE Combined Science?
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- Always check the code printed on your entry and on any paper you use.
2. A student has 15 hours. Unrevised statements: biology 12, chemistry 18, physics 30. Find the hours for each science.
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Total gaps 12 + 18 + 30 = 60. Biology 15 × 12/60 = 3 h. Chemistry 15 × 18/60 = 4.5 h. Physics 15 × 30/60 = 7.5 h. Check: 3 + 4.5 + 7.5 = 15 h.
3. What percentage of a 20 h plan is 7 h?
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7/20 = 0.35, so 35%.
4. Using Question 2, give each science’s share of the gaps as a percentage.
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Biology 12/60 = 20%. Chemistry 18/60 = 30%. Physics 30/60 = 50%. Check: 20 + 30 + 50 = 100%.
5. A student has 20 listed tasks, and 14 pass a retest. What is the mastered percentage?
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14/20 = 0.70, so 70%. Six tasks remain.
6. Three separate notes of 8 lines each cover one shared idea. A master note of 8 lines plus three 2-line hooks could replace them. How many lines are saved?
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Separate: 3 × 8 = 24. Master plus hooks: 8 + 3 × 2 = 14. Saved: 24 − 14 = 10 lines.
7. List the five items to record for a specimen paper.
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Code, exam year, route, source and the date found. The exam centre confirms the route.
8. A reaction collects 45 cm³ of gas in 90 s. Find the average rate.
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45 ÷ 90 = 0.5 cm³/s. Check: 0.5 × 90 = 45.
9. A trolley travels 60 m in 150 s. Find the average speed, and say which skill it shares with Question 8.
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60 ÷ 150 = 0.4 m/s. Check: 0.4 × 150 = 60. Both questions use change divided by time.
10. A tracker shows 70% of tasks mastered. A friend says this predicts a grade. Respond.
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The percentage describes tasks on your own list. It cannot show how Cambridge will set grade thresholds for an exam series. Use it to decide which tasks to revise next.
11. A 90-minute session is split by the gap shares in Question 4. How many minutes does each science get?
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Biology 20% of 90 = 18 min. Chemistry 30% of 90 = 27 min. Physics 50% of 90 = 45 min. Check: 18 + 27 + 45 = 90.
If you got these wrong
| Error type | Questions | Go to |
|---|---|---|
| Hours do not follow gaps, or shares do not add up | 2, 3, 4, 11 | Audit the three-science balance |
| Duplicated notes, wrong line count | 6 | Reuse a shared concept |
| Code, year or route not checked | 1, 7 | Locate a reliable current specimen |
| Mastery counted wrongly, or percentage read as a grade | 5, 10 | Track mastered tasks |
| Rate written upside down | 8, 9 | Prepare linked difficulties |
Keep wrong answers in the mistake log and retest queue, and use the scientific investigation critic for the practical side.
To work on your own errors with a teacher, see online one-to-one Combined Science tuition.