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Primary 1 Maths: Addition and Subtraction within 20 and 100 — Practice Paper 3 (10 Questions)
Primary 1 Maths: Addition and Subtraction within 20 and 100 — Practice Paper 3 (10 Questions)
Paper 3 does not repeat the earlier items: the pairs that complete ten and make-ten in both directions come first, then a column carry and a column borrow on new numbers, a three-number sum, a missing addend, and change after two purchases. Item 10 redoes the ones-digit lined up under the tens.
Quick answer 10 questions, about 20 minutes. Items 01 to 03 are number pairs for ten and make-ten, items 04 to 07 are a column carry, a column borrow, a three-number sum and a missing addend, items 08 and 09 are change and comparing two sums, and item 10 redoes the misplaced ones digit.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 questions |
| Suggested time | 20 minutes |
| Difficulty mix | Foundation 3 · Intermediate 4 · Challenge 2 · Error redo 1 |
| Chapter | Chapter: Primary 1 Maths: Addition and Subtraction within 20 and 100 — Tutor Lesson Plan |
| Level | Primary 1 |
02 Questions (10 items)
- FoundationFill in: 6 + ( ) = 10 and 8 + ( ) = 10.
- FoundationUse make-ten: 8 + 5
- FoundationUse make-ten: 17 − 9
- IntermediateWork out in columns: 38 + 46
- IntermediateWork out in columns: 52 − 27
- IntermediateWork out: 25 + 37 + 18 (pair two numbers into a multiple of ten first)
- IntermediateA number plus 46 equals 72. What is the number?
- ChallengeYou take $100 and buy a $35 pencil case and a $27 notebook. How much change?
- ChallengeWhich is larger: 47 + 38 or 52 + 33?
- Error redoWork out in columns: 45 + 8 (common slip: lining the 8 up under the tens, giving 45 + 80 = 125)
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 4 and 2 | Six needs 4 to reach ten and eight needs 2; these pairs should come out without counting. |
| 2 | 13 | 8 needs 2 to reach 10, so take 2 from the 5: 8 + 2 = 10, and the 3 left over gives 10 + 3 = 13. |
| 3 | 8 | Take 7 off 17 to reach 10, then the other 2: 10 − 2 = 8, and 8 + 9 = 17 checks it. |
| 4 | 84 | Ones: 8 + 6 = 14, write 4 and carry 1. Tens: 3 + 4 + 1 = 8, so 84. |
| 5 | 25 | Ones: 2 cannot take 7, so borrow to make 12 − 7 = 5. Tens: 5 loses 1 and becomes 4, 4 − 2 = 2, so 25. |
| 6 | 80 | 25 + 37 = 62 and adding 18 gives 80; grouping 37 + 18 = 55 first gives 25 + 55 = 80, so the order does not matter. |
| 7 | 26 | Work backwards: 72 − 46 = 26, then check 26 + 46 = 72. |
| 8 | $38 | Spend first: 35 + 27 = 62, then 100 − 62 = 38, and 38 + 62 = 100 checks it. |
| 9 | The same — both give 85 | 47 + 38 = 85 and 52 + 33 = 85, so the sums are equal: one addend is 5 bigger while the other is 5 smaller, and the total stays the same. |
| 10 | 53 | The 8 is a ones digit and belongs under the 5: 5 + 8 = 13, write 3 and carry 1; the tens give 4 + 1 = 5, so the answer is 53, not 125. |
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.
