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Primary 5 Maths: Four Operations with Decimals — Practice Paper 3 (10 Questions)
Primary 5 Maths: Four Operations with Decimals — Practice Paper 3 (10 Questions)
Paper 3 turns to judging and checking: comparing decimals, rounding, converting units, checking a product by division, change from a purchase, and the remainder when a division does not come out even.
Quick answer 10 questions, about 25 minutes. Items 01 and 02 test place value and rounding, items 03 and 05 test unit conversion, item 04 tests checking, items 07 and 08 test estimating and remainders, item 10 is the commonest slip.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 questions |
| Suggested time | 25 minutes |
| Difficulty mix | Foundation 4 · Intermediate 3 · Challenge 2 · Error redo 1 |
| Chapter | Chapter: Primary 5 Maths: Four Operations with Decimals — Tutor Lesson Plan |
| Level | Primary 5 |
02 Questions (10 items)
- FoundationWhich is larger, 0.8 or 0.75, and by how much?
- FoundationRound 4.857 to one decimal place.
- FoundationHow many millilitres are in 2.4 L?
- Foundation5.2 × 3.5 = 18.2. Check it with division.
- IntermediateSubtract 850 g from 3.6 kg. How many kilograms remain?
- IntermediateA book costs $12.80. Three books are bought and paid with $50. How much change?
- IntermediateA rope is 9.5 m long. How many 0.8 m pieces can be cut, and what is left over?
- ChallengeEstimate with 5 × 6, then compute 4.98 × 6.05 and compare.
- Challenge(7.2 − 0.45) ÷ 0.15 = ? (brackets first)
- Error redo4.5 ÷ 0.9 = ? (common slip: turning only the divisor into 9 and answering 0.5)
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 0.8 is larger, by 0.05 | Pad both to 0.80 and 0.75 before comparing: 0.80 wins. More digits does not mean a bigger number. |
| 2 | 4.9 | The second decimal is 5, so round up: 4.8 becomes 4.9, and the remaining digits are dropped. |
| 3 | 2400 mL | One litre is 1000 mL, so shift the point three places: 2.4 gives 2400. Multiplying by 100 would be wrong. |
| 4 | 18.2 ÷ 3.5 = 5.2, so the product is right | Divide the product by one factor and see whether the other comes back: scale both by 10 to get 182 ÷ 35. |
| 5 | 2.75 kg | Convert first: 850 g = 0.85 kg, then 3.6 − 0.85 = 2.75. Subtracting numbers in different units is the usual slip. |
| 6 | $11.6 | First 12.80 × 3 = 38.40, then 50.00 − 38.40 = 11.60. Writing 50.00 keeps the borrowing straight. |
| 7 | 11 pieces, 0.7 m left | 9.5 ÷ 0.8 = 11.875, so take 11 whole pieces and the remainder is 9.5 − 8.8 = 0.7 m. Twelve pieces would be too long. |
| 8 | 30.129 (estimate 30, off by -0.129) | 4.98 ≈ 5 and 6.05 ≈ 6 give 30; exactly, 498 × 605 = 301290 with four decimal places is 30.129, an error of only 0.129. |
| 9 | 45 | Inside: 7.2 pads to 6.75, then multiply both by 100 to get 675 ÷ 15 = 45. Estimating 7 ÷ 0.15 ≈ 46 first keeps it sane. |
| 10 | 5 | One decimal place in the divisor means both numbers multiply by 10: 45 ÷ 9 = 5. A divisor below 1 always gives a larger answer than 4.5. |
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.
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.
