Primary 4 Mathematics Practice Paper 3

TuitionGoWhere Practice Paper - Mathematics Primary 4 (Answer Key)

Subject: Mathematics
Level: Primary 4
Paper: Practice Paper — Whole Numbers (Numbers up to 100,000)
Total Marks: 50

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Section A: Multiple-Choice Questions (10 × 1 mark = 10 marks)

1. Answer: (2)
In 64,289, the digits from left to right are: 6 (ten thousands), 4 (thousands), 2 (hundreds), 8 (tens), 9 (ones). The digit in the thousands place is 4.

2. Answer: (4)
In 57,342, the digit 7 is in the thousands place. Its value is 7 × 1,000 = 7,000.

3. Answer: (1)
83,006 = 80,000 + 3,000 + 6 = Eighty-three thousand and six.
Note: "Eighty-three thousand and sixty" would be 83,060. "Eight thousand three hundred and six" would be 8,306.

4. Answer: (2)
To round 47,562 to the nearest hundred: look at the tens digit (6). Since 6 ≥ 5, round up the hundreds digit from 5 to 6.
47,562 → 47,600.

5. Answer: (3)
A number rounds to 32,000 when rounded to the nearest thousand if it is between 31,500 and 32,499 (inclusive of 31,500, exclusive of 32,500).

• 31,450 → rounds to 31,000
• 31,550 → rounds to 32,000 ✓
• 32,450 → rounds to 32,000 ✓
• 32,550 → rounds to 33,000
  Both (2) and (3) are correct, but typically only one option is intended. 32,450 is closer to the upper bound. However, 31,550 is the smallest number that rounds up to 32,000. In standard Singapore exam practice, 31,550 is the classic "smallest number that rounds to 32,000" answer.
  Marking note: If both (2) and (3) appear as options, (2) 31,550 is the intended answer as it tests the lower boundary.

6. Answer: (1)
50,000 + 3,000 + 400 + 20 + 7 = 53,427.

7. Answer: (1)
84,500 − 29,876 = 54,624.
Working:

  84,500
− 29,876
--------
  54,624

8. Answer: (1)
324 × 18 = 324 × (10 + 8) = 3,240 + 2,592 = 5,832.
Alternative: 324 × 2 = 648; 648 × 9 = 5,832.

9. Answer: (1)
7,632 ÷ 6 = 1,272.
Check: 1,272 × 6 = 7,632.

10. Answer: (2)
A number rounds to 12,350 (nearest ten) if it is between 12,345 and 12,354 inclusive.

• 12,344 → rounds to 12,340
• 12,346 → rounds to 12,350 ✓
• 12,355 → rounds to 12,360
• 12,356 → rounds to 12,360

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Section B: Short-Answer Questions (10 × 2 marks = 20 marks)

11. Answer: 90,000 (or "ninety thousand") [2]
Working: In 92,475, the digit 9 is in the ten thousands place.
Value = 9 × 10,000 = 90,000.
Mark allocation: 1 mark for identifying place (ten thousands), 1 mark for correct value.

12. Answer: 64,309 [2]
Working: Sixty-four thousand = 64,000; three hundred = 300; nine = 9.
64,000 + 300 + 9 = 64,309.
Common mistake: Writing 64,039 (omitting the hundreds place) or 64,390 (confusing tens and hundreds).

13. Answer: 48,029 ; 48,209 ; 48,290 ; 48,902 [2]
Working: Compare thousands (all 48), then hundreds: 0 < 2 < 2 < 9. For the two with 2 hundreds, compare tens: 0 < 9.
Order: 48,029 < 48,209 < 48,290 < 48,902.
Mark allocation: 1 mark for correct first/last, 2 marks for fully correct order.

14. Answer: 23,500 [2]
Working: The pattern decreases by 500 each time.
25,000 − 500 = 24,500
24,500 − 500 = 24,000
24,000 − 500 = 23,500
23,500 − 500 = 23,000 ✓

15. Answer: 68,000 [2]
Working: To round 68,493 to the nearest thousand, look at the hundreds digit (4). Since 4 < 5, round down.
68,493 → 68,000.
Common mistake: Rounding up to 69,000 by looking at the tens digit instead of hundreds.

16. Answer: 64,161 [2]
Working:

  38,472
+ 25,689
--------
  64,161

Mark allocation: 1 mark for correct method/working, 1 mark for correct answer.

17. Answer: 30,124 [2]
Working:

  50,000
− 19,876
--------
  30,124

Check: 30,124 + 19,876 = 50,000 ✓

18. Answer: 38,943 [2]
Working: 4,327 × 9

   4,327
×      9
--------
  38,943

4,327 × 10 = 43,270; 43,270 − 4,327 = 38,943 (alternative mental method).

19. Answer: 1,224 [2]
Working: 8,568 ÷ 7
7 × 1,000 = 7,000; remainder 1,568
7 × 200 = 1,400; remainder 168
7 × 20 = 140; remainder 28
7 × 4 = 28; remainder 0
Answer = 1,000 + 200 + 20 + 4 = 1,224.
Check: 1,224 × 7 = 8,568 ✓

20. Answer: 45,649 [2]
Working: A number rounds to 45,600 (nearest hundred) if it is from 45,550 to 45,649 inclusive.
The greatest possible value is 45,649.
Mark allocation: 1 mark for understanding range (45,550–45,649), 1 mark for correct greatest value.

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Section C: Structured / Long-Answer Questions (5 × 4 marks = 20 marks)

21.
(a) Answer: 7,800 [1]
Working: 7,804 rounded to nearest hundred → look at tens digit (0). Since 0 < 5, round down. 7,804 → 7,800.

(b) Answer: 20,652 [2]
Working: 28,456 − 7,804 = 20,652.

  28,456
−  7,804
--------
  20,652

Mark allocation: 1 mark for correct subtraction setup/working, 1 mark for correct answer.

(c) Answer: Twenty thousand, six hundred and fifty-two [1]
Working: 20,652 in words = Twenty thousand, six hundred and fifty-two.
Note: "and" is used before the last two digits in Singapore convention.

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22.
(a) Answer: National Museum of Singapore [1]
Reasoning: Compare 48,732 ; 35,289 ; 42,156. The greatest is 48,732 (National Museum).

(b) Answer: 126,177 [2]
Working:

  48,732
  35,289
+ 42,156
--------
 126,177

Mark allocation: 1 mark for correct addition of all three numbers (working shown), 1 mark for correct total.

(c) Answer: 13,443 [1]
Working: 48,732 − 35,289 = 13,443.

  48,732
− 35,289
--------
  13,443

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23.
(a) Answer: 9,685 [1]
Working: February = January + 1,235 = 8,450 + 1,235 = 9,685.

(b) Answer: 19,370 [1]
Working: March = 2 × February = 2 × 9,685 = 19,370.
Check: 9,685 × 2 = 19,370.

(c) Answer: 37,505 [2]
Working: Total = January + February + March = 8,450 + 9,685 + 19,370 = 37,505.

   8,450
   9,685
+ 19,370
--------
  37,505

Mark allocation: 1 mark for correct February and March values (or correct method), 1 mark for correct total with working.

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24.
(a) Answer: $61,130** [1] *Working:*$48,750 + $12,380 = **$61,130.

  48,750
+ 12,380
--------
  61,130

(b) Answer: $23,870** [2] *Working:*$85,000 − $61,130 = **$23,870.

  85,000
− 61,130
--------
  23,870

Mark allocation: 1 mark for correct subtraction method, 1 mark for correct answer.

(c) Answer: No, he would not have enough money left. He has $23,870 left, but the motorcycle costs$15,000. Wait — $23,870 >$15,000, so actually YES, he has enough.
Correction: $23,870 −$15,000 = $8,870 remaining. So Yes, he has enough money left.
Mark allocation: 1 mark for correct comparison and conclusion with correct reasoning.
Common mistake: Students may miscalculate the remainder in (b) and give an incorrect conclusion here. Follow-through marking applies: if (b) is wrong but (c) correctly follows from their (b), award the mark.

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25.
(a) Answer: 70,000 (or "seventy thousand") [1]
Working: In 178,943, the digit 7 is in the ten thousands place.
Value = 7 × 10,000 = 70,000.
Note: The postal code is 6 digits (178943), so places are: 1 (hundred thousands), 7 (ten thousands), 8 (thousands), 9 (hundreds), 4 (tens), 3 (ones).

(b) Answer: 180,000 [1]
Working: 178,943 rounded to nearest ten thousand → look at thousands digit (8). Since 8 ≥ 5, round up the ten thousands digit from 7 to 8.
178,943 → 180,000.

(c) Answer: 188,500 [2]
Working: A number rounds to 189,000 (nearest thousand) if it is from 188,500 to 189,499 inclusive.
The smallest possible value is 188,500.
Mark allocation: 1 mark for identifying the lower bound (188,500), 1 mark for correct answer.
Common mistake: Answering 188,000 (rounding down instead of finding the minimum that rounds up).

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END OF ANSWER KEY
Total Marks: 50