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Primary 4 Maths: Factors and Multiples — Practice Paper 4 (10 Questions)
Primary 4 Maths: Factors and Multiples — Practice Paper 4 (10 Questions)
Paper 4 closes the set: factor pairs up to a number as rich as 72, then the H.C.F. and the L.C.M. once more with 36 and 54 and with 18 and 24. The last item redoes the factor list that drops 1 and the number itself.
Quick answer 10 questions, about 25 minutes. Items 01 to 03 cover the factors of 45, the first multiples of 7 and a prime check on 91; items 04 to 06 cover the twelve factors of 72, the H.C.F. of 36 and 54 and the L.C.M. of 10 and 15; items 07 to 09 cover both values for 18 and 24, stationery packets (H.C.F.) and duty days (L.C.M.); item 10 redoes the missing factor pair.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 questions |
| Suggested time | 25 minutes |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: Primary 4 Maths: Factors and Multiples (H.C.F. and L.C.M.) — Tutor Lesson Plan |
| Level | Primary 4 |
02 Questions (10 items)
- FoundationList all the factors of 45.
- FoundationWrite the first six multiples of 7, smallest first.
- FoundationIs 91 a prime number? Give a reason.
- IntermediateList all the factors of 72 and say how many there are.
- IntermediateFind the H.C.F. of 36 and 54.
- IntermediateFind the L.C.M. of 10 and 15.
- ChallengeFind the H.C.F. and the L.C.M. of 18 and 24.
- Challenge84 pencils and 60 rulers are shared into identical stationery packets with the same contents. What is the greatest number of packets, and what goes into each?
- ChallengeOne pupil is on duty every 8 days and another every 12 days. Both are on duty today. After how many days will they next be on duty together?
- Error redoA student lists the factors of 36 as 2, 3, 4, 6, 9, 12 and 18. What was left out, and how many factors does 36 have?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 1, 3, 5, 9, 15, 45 (6 factors) | Pair them as 1 × 45, 3 × 15 and 5 × 9: three pairs make 6 factors, and 1 and the number itself are always included. |
| 2 | 7, 14, 21, 28, 35, 42 | Multiples come from multiplying 7 by 1 up to 6; every one divides by 7 with no remainder. |
| 3 | No, 91 = 7 × 13 | 91 ÷ 7 = 13, so 91 has four factors (1, 7, 13 and 91) and is composite. |
| 4 | 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72 (12 factors) | Pair them as 1 × 72, 2 × 36, 3 × 24, 4 × 18, 6 × 12 and 8 × 9: six pairs make 12 factors. |
| 5 | 18 | Short division leaves 2, 3, 3 in the left column and only that column is multiplied: 2 × 3 × 3 = 18, and 36 ÷ 18 = 2 while 54 ÷ 18 = 3. |
| 6 | 30 | The left column holds 5 and the bottom row holds 2 and 3, so 5 × 2 × 3 = 30; 30 ÷ 10 = 3 and 30 ÷ 15 = 2. |
| 7 | H.C.F. = 6, L.C.M. = 72 | Short division leaves 2 and 3 on the left, so the H.C.F. is 6; the bottom row holds 3 and 4, giving 6 × 12 = 72. The check is 6 × 72 = 432 = 18 × 24. |
| 8 | 12 packets, each with 7 pencils and 5 rulers | The greatest number of identical packets is the H.C.F.: H.C.F.(84, 60) = 12, and 84 ÷ 12 = 7 while 60 ÷ 12 = 5, so nothing is left over. |
| 9 | 24 days | Meeting again is the L.C.M.: L.C.M.(8, 12) = 24 days. The product 8 × 12 = 96 is a common multiple, but not the smallest one. |
| 10 | 1 and 36 were left out; 9 factors in all | 1 and the number itself are always factors, so the full list has 9 entries: 1, 2, 3, 4, 6, 9, 12, 18 and 36. Pairing 1 × 36, 2 × 18, 3 × 12, 4 × 9 and 6 × 6 checks the list. |
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.
