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S3 Maths: Significant Figures and Percentage Error (Paper 1 (basics))
S3 Maths: Significant Figures and Percentage Error (Paper 1 (basics))
Paper 1 (basics): ten questions on significant figures and percentage error, 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: S3 Maths: Significant Figures and Percentage Error |
| Level | S3 |
02 Questions (10 items)
- FoundationHow many significant figures does 0.00456 have?
- FoundationHow many significant figures does 3.080 have?
- FoundationRound 1234 to three significant figures.
- IntermediateRound 0.02567 to two significant figures.
- IntermediateRound 5.678 to one decimal place.
- IntermediateA pencil measures 12.4 cm to the nearest 0.1 cm. What is the maximum absolute error?
- ChallengeA parcel has true mass 48 g and its maximum absolute error is 0.5 g. Find the percentage error to two decimal places.
- ChallengeHow is percentage error related to relative error?
- ChallengeRound 18.75 to three significant figures.
- Error redoError clinic: a student says 0.0305 has five significant figures. What is wrong?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | Three | Leading zeros only show place value and do not count, so the figures 4, 5 and 6 give three significant figures. |
| 2 | Four | A trailing zero after the decimal point counts, so 3, 0, 8 and 0 give four significant figures. |
| 3 | 1230 | The third significant figure is 3 and the next digit is 4, so no rounding up is needed and one zero keeps the place value. |
| 4 | 0.026 | The first two significant figures are 2 and 5, and the next digit 6 rounds the 5 up to 6. |
| 5 | 5.7 | The first decimal digit is 6 and the next digit 7 rounds it up to 7. |
| 6 | 0.05 cm | The maximum absolute error is half the smallest division, 0.1 divided by 2, which is 0.05 cm. |
| 7 | 1.04% | Percentage error equals 0.5 divided by 48 times one hundred per cent, which is 1.0416 per cent and rounds to 1.04 per cent. |
| 8 | Percentage error equals relative error times one hundred per cent | Relative error is a ratio with no unit, and multiplying it by one hundred gives the percentage error. |
| 9 | 18.8 | The third significant figure is 7 and the next digit 5 rounds it up to 8. |
| 10 | It has three significant figures | The two leading zeros only mark place value, so only 3, 0 and 5 count as significant figures. |
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.
Ask first whether a zero counts: zeros between non-zero digits, or trailing zeros after a decimal point, do count, while leading zeros that only mark place value do not. For error questions, write the maximum absolute error as half the smallest scale division, then divide by the true value and multiply by one hundred per cent.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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