Primary 1 Mathematics Practice Paper 3

TuitionGoWhere Practice Paper - Mathematics Primary 1 (Version 3)

Answer Key and Marking Scheme

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Total Marks: 40 marks

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Section A: Counting and Number Recognition (10 marks)

1. 13 stars [2 marks]

Working/Explanation: Count each star one by one: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13. There are two rows of 5 stars (which makes 10) plus 3 more stars, so 10 + 3 = 13. Students may also count by grouping: five, ten, and three more.

Common mistake: Rushing and double-counting or skipping a star. Encourage students to touch each star or mark it as they count.

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2. 17 apples [2 marks]

Working/Explanation: The image shows 17 apples scattered in a group. Students should count carefully from 1 to 17, touching or pointing to each apple as they count. The apples are a mix of red and green, but students count all apples regardless of color.

Expected visual features: 17 visible apples, some red and some green, arranged so none completely hide another. Students may group them mentally (e.g., ten and seven more) to help counting.

Common mistake: Counting only one color of apples. Remind students to count ALL objects in the picture.

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3. 30 [1 mark]

Working/Explanation: "Just after 29" means the next number when counting forward: 29, 30. When we count, we add 1 each time. So 29 + 1 = 30.

Key concept: Number sequence and counting forward by 1.

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4. 49 [1 mark]

Working/Explanation: "Just before 50" means the number that comes right before it when counting: 48, 49, 50. We subtract 1 from 50: 50 − 1 = 49.

Key concept: Number sequence and counting backward by 1.

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5. 27, 28 [2 marks]

Working/Explanation: The sequence counts up by 1 each time: 24, 25, 26, so next is 26 + 1 = 27, then 27 + 1 = 28, then 29, 30. Check: 24, 25, 26, 27, 28, 29, 30 ✓

Mark breakdown: 1 mark for each correct missing number.

5(b) The numbers go up by 1 each time / The numbers increase by 1 / It is counting forward by ones [2 marks]

Working/Explanation: To find the pattern, look at the difference between consecutive numbers: 25 − 24 = 1, 26 − 25 = 1, 29 − 28 = 1, 30 − 29 = 1. Each number is 1 more than the previous number. This is called a counting pattern or sequence with a constant difference of 1.

Acceptable answers: "Add 1 each time," "the numbers get bigger by 1," "counting by ones," "increasing by 1."

Mark breakdown: 2 marks for clear explanation of +1 pattern; 1 mark for partial description.

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Section B: Place Value (10 marks)

6(a) 3 tens [1 mark]

Working/Explanation: In the number 38, the digit 3 is in the tens place. The image shows 3 ten-sticks (long rods), where each ten-stick represents 10. So there are 3 tens in 38.

Key concept: Place value - the position of a digit tells us its value. In 38: 3 is in the tens place, 8 is in the ones place.

6(b) 8 ones [1 mark]

Working/Explanation: In the number 38, the digit 8 is in the ones place. The image shows 8 one-cubes (single cubes). So there are 8 ones in 38.

Expected visual features: 3 ten-sticks and 8 one-cubes clearly shown and labeled.

Extension: 38 = 3 tens + 8 ones = 30 + 8 = 38

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7. 60 (or 6 tens) [2 marks]

Working/Explanation: In 65, the digit 6 is in the tens place. The value of a digit in the tens place is: digit × 10. So 6 × 10 = 60. The value is 60, not just 6.

Common mistake: Answering "6" instead of "60." This confuses the digit (the symbol 6) with the value (what it represents, which is 60). The question asks for "value," not "digit."

Key concept: Value = digit × place value. For tens place: value = digit × 10.

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8. 7 (or 7 ones) [2 marks]

Working/Explanation: In 47, the digit 7 is in the ones place. The value of a digit in the ones place is: digit × 1. So 7 × 1 = 7. The value is 7.

Note: Some students may say "7 ones" - this is correct and shows deeper understanding. Either "7" or "7 ones" or "7 ones = 7" is acceptable.

Key concept: In the ones place, the digit represents itself (digit × 1).

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9. 52 [2 marks]

Working/Explanation:

• 5 tens = 5 × 10 = 50
• 2 ones = 2 × 1 = 2
• Total: 50 + 2 = 52

We can also write this as: 5 tens and 2 ones = 52

Method: Write the tens digit first, then the ones digit. Place value tells us: tens digit goes on the left, ones digit goes on the right.

Common mistake: Writing 25 (reversing digits) or writing 502 (not understanding place value). Remind students: tens always on the left, ones on the right.

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10. 83, 80 [2 marks]

Working/Explanation: We need to find numbers where 8 is in the tens place (the left digit).

• 83: 8 is in tens place ✓, 3 is in ones place
• 38: 3 is in tens place ✗, 8 is in ones place
• 58: 5 is in tens place ✗, 8 is in ones place
• 80: 8 is in tens place ✓, 0 is in ones place
• 28: 2 is in tens place ✗, 8 is in ones place

So circle 83 and 80.

Marking: 2 marks for both correct; 1 mark for one correct with one incorrect (or missing the second); 0 marks if only incorrect answers circled.

Key concept: The tens place is always the left digit in a two-digit number.

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Section C: Comparing and Ordering Numbers (10 marks)

11. 45 [2 marks]

Working/Explanation: Compare 54 and 45 using place value:

• 54: 5 tens and 4 ones = 50 + 4
• 45: 4 tens and 5 ones = 40 + 5

Compare tens first: 5 tens > 4 tens, so 54 > 45, which means 45 < 54.

Therefore, 45 is smaller.

Method: Always compare the tens digit first. The number with the smaller tens digit is the smaller number. If tens are equal, compare ones.

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12. 27, 37, 72, 73 [2 marks]

Working/Explanation:

• First, look at tens digits: 27 and 37 have 2 tens and 3 tens (smaller), while 72 and 73 have 7 tens (bigger).
• Compare 27 and 37: 2 tens < 3 tens, so 27 < 37
• Compare 72 and 73: both have 7 tens, so compare ones: 2 < 3, so 72 < 73

Order: 27, 37, 72, 73

Mark breakdown: 2 marks for fully correct order; 1 mark if only one number out of place; 0 marks for more errors.

Method tip: When ordering, first group by tens digit, then order within each group.

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13(a) Tank B [1 mark]

Working/Explanation: By counting or visual comparison: Tank A has 15 fish, Tank B has 23 fish. Since 23 > 15, Tank B has more fish. Students may count or see that Tank B's group looks larger.

Expected visual features: Tank A with 15 visible fish, Tank B with 23 visible fish. No number labels on tanks.

13(b) 8 more fish [2 marks]

Working/Explanation:

• Tank A: 15 fish
• Tank B: 23 fish
• Difference: 23 − 15 = 8

Or using counting on: from 15, count up to 23: 16, 17, 18, 19, 20, 21, 22, 23. That's 8 numbers, so 8 more.

Show your working: 23 − 15 = 8, or 15 + ? = 23, so ? = 8

Common mistake: Answering "23" (the total in B) instead of "8 more." Read carefully: "how many MORE" asks for difference, not total.

Mark breakdown: 1 mark for correct method shown; 1 mark for correct answer of 8.

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14(a) Ben [1 mark]

Working/Explanation:

• Ben: 34 stickers = 3 tens and 4 ones = 30 + 4
• Siti: 43 stickers = 4 tens and 3 ones = 40 + 3

Compare tens: 3 tens < 4 tens, so 34 < 43. Ben has fewer stickers.

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14(b) less than (or 34 < 43) [1 mark]

Working/Explanation: Since Ben (34) has fewer than Siti (43), we say 34 is less than 43. The symbol < means "less than," with the small point facing the smaller number.

Key concept: < means less than, > means greater than. The symbol opens toward the bigger number.

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15. < [1 mark]

Working/Explanation: 56 vs 65:

• 56: 5 tens and 6 ones
• 65: 6 tens and 5 ones

5 tens < 6 tens, so 56 < 65.

15(b) = [1 mark]

Working/Explanation: 38 vs 38. These are the same number. When two numbers are equal, we use the = sign.

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Section D: Number Patterns and Ordinal Numbers (10 marks)

16. 25, 30, 35 [2 marks]

Working/Explanation: Find the pattern: 10 − 5 = 5, 15 − 10 = 5, 20 − 15 = 5. The pattern increases by 5 each time (counting in fives, or the 5 times table).

Continue: 20 + 5 = 25, 25 + 5 = 30, 30 + 5 = 35.

Check: 5, 10, 15, 20, 25, 30, 35 ✓

Mark breakdown: 2 marks for all three correct; 1 mark for two correct; 0 marks for one or zero correct.

Key concept: 5 times table: 5, 10, 15, 20, 25, 30, 35, ...

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17. 54 [2 marks]

Working/Explanation: Find the constant difference:

• 45 − 42 = 3
• 48 − 45 = 3
• 51 − 48 = 3

The pattern increases by 3 each time. So: 51 + 3 = 54. Check: 54 + 3 = 57 ✓

Sequence: 42, 45, 48, 51, 54, 57

17(b) 3 [1 mark]

Working/Explanation: As shown above, each number is 3 more than the previous number. This is found by subtracting consecutive pairs.

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18(a) Carl [1 mark]

Working/Explanation: From the left (starting from Ali): 1st-Ali, 2nd-Beth, 3rd-Carl. So Carl is in 3rd position.

Expected visual features: Queue from left to right: Ali (red), Beth (blue), Carl (green cap), Dana (yellow), Evan (black), Fay (pink), Gina (orange), Hock (purple). The 3rd child from left wears a green cap and is labeled/identifiable as Carl.

Key concept: Ordinal numbers tell position, not quantity. "3rd" means the one in position 3, not 3 items total.

18(b) 4th [1 mark]

Working/Explanation: Counting from the left: 1st-Ali, 2nd-Beth, 3rd-Carl, 4th-Dana. Dana is in 4th position.

Common mistake: Counting Dana herself (saying "3rd" because there are 3 people before her). Remind students: the position number includes counting that person too.

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19. 10 children [2 marks]

Working/Explanation:

• Mei finished 6th: this means 5 runners finished before her (1st, 2nd, 3rd, 4th, 5th)
• 3 runners finished after her (7th, 8th, 9th places)
• Total: 5 (before) + 1 (Mei) + 3 (after) = 9 runners? No, careful counting:

Actually: Places 1, 2, 3, 4, 5, 6(Mei), 7, 8, 9. That's 9 places? But 6 + 3 = 9 runners after includes Mei? No.

Correct method: If Mei is 6th, there are 5 people ahead. 3 people finished after her. Total = 5 + 1 + 3 = 9? Or: the last finisher is in position 6 + 3 = 9th place. So there are 9 runners total?

Wait - let me recalculate: 6th place means 5 people before. 3 people after. Total = 5 + 1 (Mei) + 3 = 9.

Actually, let me verify: positions 1,2,3,4,5,6,7,8,9 = 9 positions. Yes, 9 children.

But the answer should be: 6 + 3 = 9. The 3 runners after Mei are in positions 7, 8, 9. So the last position is 9th, meaning 9 children total.

Hmm, let me re-read: "Mei finished in 6th place. There were 3 runners who finished after her."

If Mei is 6th, the next is 7th, then 8th, then 9th. That's 3 runners after her (7th, 8th, 9th). Total children = 9.

Working:

• Mei: 6th place
• After Mei: 7th, 8th, 9th = 3 runners
• Total positions = 9
• Total children = 9

Alternatively: 6 + 3 = 9.

Common mistake: Answering 6 + 3 = 9 but not understanding why, or saying "9th" instead of "9 children." The question asks "how many children," so answer is 9, not 9th.

Actually, let me double-check my own arithmetic: 6 + 3 = 9. Yes. But wait, does "3 runners finished after her" include people in positions 7, 8, 9? That's 3 people. So last place is 9th. 9 positions = 9 children.

Hmm, but I want to make sure. Let me recount: if Mei is 6th, she is ONE person. Before her: positions 1,2,3,4,5 = 5 people. After her: 3 people = positions 7,8,9. Total: 5 + 1 + 3 = 9. ✓

Mark breakdown: 1 mark for correct method (showing 6 + 3 or counting positions); 1 mark for correct answer 9.

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20(a) 54, 66, 68, 70 [2 marks]

Working/Explanation: The hundreds chart shows numbers 51-70 in a 10-column grid. Reading left to right, top to bottom:

• Row 1: 51, 52, 53, [54], 55, 56, 57, 58, 59, 60
• Row 2: 61, 62, 63, 64, 65, [66], [67], [68], 69, [70]

Wait, let me check: blank spaces at 54, 66, 68, 70.

Expected visual features: Grid with 10 columns. Missing numbers should be filled by counting pattern.

Mark breakdown: 2 marks for all four correct; 1 mark for three correct; 0 marks for fewer.

20(b) 65 [1 mark]

Working/Explanation: On a hundreds chart, moving down one row adds 10. From 55, move down to the number directly below: 55 + 10 = 65.

Alternatively, 55 is in position: row 1, column 6. Directly below is row 2, column 6 = 65.

Key concept: In a hundreds chart, numbers increase by 10 when moving down one row, and by 1 when moving right one column.

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Mark Summary

Section	Marks
Section A (Q1-5)	10
Section B (Q6-10)	10
Section C (Q11-15)	10
Section D (Q16-20)	10
Total	40

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This practice paper is syllabus-aligned content generated by TuitionGoWhere AI. It is not derived from official past-year examination papers. It is designed for practice and skill-building purposes.