Primary 3 Mathematics Semestral Assessment 2 (End of Year) Paper 4

TuitionGoWhere Exam Practice (AI) — Answer Key

Primary 3 Mathematics — SA2 Practice Paper — Version 4 of 5

Total Marks: 80

SECTION A: Multiple Choice Questions (15 marks)

1. Answer: (b) 0

• In 7,056: 7 is thousands, 0 is hundreds, 5 is tens, 6 is ones.
• Common mistake: Choosing 5 (tens place) instead of reading carefully.

2. Answer: (d) 8,000

• The digit 8 is in the thousands place.
• Value = 8 × 1,000 = 8,000.

3. Answer: (b) 4,052

• Compare thousands: all have 4.
• Compare hundreds: 0 < 2 < 5, so 4,052 is smallest.

4. Answer: (a) 5,128

• 5 thousands = 5,000
• 12 tens = 120
• 8 ones = 8
• Total: 5,000 + 120 + 8 = 5,128

5. Answer: (b) 7,289

• 6,789 + 500 = 7,289.

6. Answer: (c) 4,600

• 4,567: tens digit is 6, so round up.
• 4,567 → 4,600 (nearest hundred).

7. Answer: (b) 5,670

• Smaller number = 8,120 − 2,450 = 5,670.

8. Answer: (a) 3,210; 3,120; 3,021; 3,012

• Compare from left: 3,210 > 3,120 > 3,021 > 3,012.

9. Answer: (c) 6,245

• 2,456 + 3,789:
  • Ones: 6 + 9 = 15 (write 5, carry 1)
  • Tens: 5 + 8 + 1 = 14 (write 4, carry 1)
  • Hundreds: 4 + 7 + 1 = 12 (write 2, carry 1)
  • Thousands: 2 + 3 + 1 = 6
• Answer: 6,245

10. Answer: (c) 1,800

• 1st: 1,050
• 2nd: 1,050 + 250 = 1,300
• 3rd: 1,300 + 250 = 1,550
• 4th: 1,550 + 250 = 1,800

11. Answer: (b) 2,824

• 1,248 + 1,576:
  • 8 + 6 = 14 (write 4, carry 1)
  • 4 + 7 + 1 = 12 (write 2, carry 1)
  • 2 + 5 + 1 = 8
  • 1 + 1 = 2
• Answer: 2,824

12. Answer: (b) 4,544

• 7,000 − 2,456:
  • Need to borrow: 7,000 = 6,990 + 10 (after multiple borrows)
  • Or check: 4,544 + 2,456 = 7,000 ✓
• Answer: 4,544

13. Answer: (d) 8,888 > 8,880

• (a) False: 2,345 < 2,435
• (b) False: 5,060 ≠ 5,006
• (c) False: 3,210 > 3,120
• (d) True: 8,888 > 8,880

14. Answer: (c) 40

• 3,240 ÷ 100 = 32 remainder 40
• Or: 32 × 100 = 3,200; 3,240 − 3,200 = 40
• Answer: 40 cookies left over

15. Answer: (a) 400 (Note: options show (a) and (d) same; intended answer is 400)

• 3,600 ÷ 9 = 400
• Check: 400 × 9 = 3,600 ✓

SECTION B: Short Answer Questions (40 marks)

16. Five thousand and seventy-eight [2 marks]

• 5 = five thousand, 0 = no hundreds (skip), 7 = seventy, 8 = eight.
• Common mistake: "Five thousand seventy-eight" (missing "and").

17. 9,065 [2 marks]

• Nine thousand = 9,000; sixty-five = 65.
• Total: 9,000 + 65 = 9,065.

18. 8 [2 marks]

• In 9,803: 9=9000, 8=800, 0=0, 3=3.
• The digit 8 is in the hundreds place.

19. 6,025; 6,052; 6,205; 6,520 [2 marks]

• All have 6 thousands.
• Compare hundreds: 0 < 2 < 5, so 6,025 and 6,052 come before 6,205 and 6,520.
• Then 6,025 < 6,052 (25 < 52), and 6,205 < 6,520.

20. 7,412 [2 marks]

• 4,567 + 2,845:
  • 7 + 5 = 12 (write 2, carry 1)
  • 6 + 4 + 1 = 11 (write 1, carry 1)
  • 5 + 8 + 1 = 14 (write 4, carry 1)
  • 4 + 2 + 1 = 7
• Answer: 7,412

21. 3,544 [2 marks]

• 7,000 − 3,456:
  • Multiple borrowing needed
  • Check: 3,544 + 3,456 = 7,000 ✓
• Answer: 3,544

22. 2,870 [2 marks]

• Difference = 8,100 − 5,230
  • 0 − 0 = 0
  • Need borrow: 10 − 3 = 7
  • Need borrow: 0 − 2, can't, so borrow again: 10 − 2 = 8 (after adjustments)
  • 7 − 5 = 2
• Or: 8,100 − 5,230 = 2,870
• Answer: 2,870

23. 1,950 [2 marks]

• Pattern: Add 250 each time.
• 1,700 + 250 = 1,950
• Check: 1,950 + 250 = 2,200 ✓

24. Nearest thousand: 8,000 [1 mark]; Nearest hundred: 8,300 [1 mark]

• Nearest thousand: 8,349 → 8,000 (349 < 500, round down)
• Nearest hundred: 8,349 → 8,300 (49 < 50, round down)
• Total: 2 marks

25. 4,450 to 4,549 [2 marks]

• Rounding to nearest hundred: 4,500 means range is 4,450 to 4,549.
• At 4,450 exactly: rounds up to 4,500 (standard rounding).
• At 4,549: rounds down to 4,500.
• Answer: All whole numbers from 4,450 to 4,549 inclusive (100 numbers).

26. 5,566 bottles [4 marks]

• January: 2,345 bottles
• February: 2,345 + 876 = 3,221 bottles [1 mark for Feb]
• Total: 2,345 + 3,221 = 5,566 bottles [3 marks]
• Alternative mark scheme: Correct method for Feb (1m), correct Feb value (1m), correct method for total (1m), correct final answer (1m).

27. [4 marks]

Generated diagram for 27.

• Part A + Part B = Total
• Part A = 8,240 − 3,568 [1 mark for correct method]
• 8,240 − 3,568:
  • 0 − 8: borrow, 10 − 8 = 2
  • 3 − 6 (after borrow): borrow, 13 − 6 = 7
  • 1 − 5 (after borrow): borrow, 11 − 5 = 6
  • 7 − 3 = 4
• Answer: 4,672 [3 marks, or 1m working + 2m correct answer]

28. 1,676 stickers [4 marks]

• Given: 1,248 + 1,576 = 2,824 stickers given away [1 mark]
• Left: 5,000 − 2,824 [1 mark]
• 5,000 − 2,824:
  • Multiple borrowing: 5,000 = 4,999 + 1 (after borrows)
  • = 2,176? No: 5,000 − 2,824 = 2,176
  • Let me recheck: 2,824 + 2,176 = 5,000? 2,824 + 2,000 = 4,824; +176 = 5,000 ✓
• Wait, let me recalculate: 5,000 − 2,824:
  • 0 − 4: borrow, 10 − 4 = 6
  • 9 − 2 = 7
  • 9 − 8 = 1
  • 4 − 2 = 2
• Answer: 2,176
• Hmm, but let me check again: 1,248 + 1,576 = 2,824. 5,000 − 2,824 = 2,176.

Actually rechecking: 5,000 − 2,824:

• 0000 − 2824, borrow from 5:
• 10 − 4 = 6
• 9 − 2 = 7
• 9 − 8 = 1
• 4 − 2 = 2 = 2,176

But 2,824 + 2,176 = 5,000? 2,824 + 2,176:

• 4 + 6 = 10
• 2 + 7 + 1 = 10
• 8 + 1 + 1 = 10
• 2 + 2 + 1 = 5 = 5,000 ✓

Answer: 2,176 [2 marks for method and calculation]

Wait, let me re-read the question: 1,248 and 1,576.

1,248 + 1,576:

• 8 + 6 = 14, write 4, carry 1
• 4 + 7 + 1 = 12, write 2, carry 1
• 2 + 5 + 1 = 8
• 1 + 1 = 2 = 2,824 ✓

5,000 − 2,824 = 2,176

Final Answer: 2,176 stickers

29. [4 marks total]

Generated chart for 29.

(a) 750 more books [2 marks]

• Class 3B: 2,000 books
• Class 3C: 1,250 books
• Difference: 2,000 − 1,250 = 750 books [1m method, 1m answer]

(b) 6,500 books [2 marks]

• Total: 1,500 + 2,000 + 1,250 + 1,750
• 1,500 + 2,000 = 3,500
• 1,250 + 1,750 = 3,000
• 3,500 + 3,000 = 6,500 books [1m method, 1m answer]

30. 3,100 [4 marks]

• Original number: 6,800 − 2,450 = 4,350 [2 marks for finding original number]
• 4,350 − 1,250 = 3,100 [2 marks for final calculation]
• Alternative: Could also solve as 6,800 − 2,450 − 1,250 = 6,800 − 3,700 = 3,100 if student sees shortcut.

SECTION C: Problem Solving (25 marks)

31. [5 marks]

Generated diagram for 31.

(a) 500 [2 marks]

• Total distance A to D: 3,000 − 1,500 = 1,500 [1 mark]
• Three equal intervals: 1,500 ÷ 3 = 500 [1 mark]

(b) 2,500 [1 mark]

• C = A + 3 × 500? No, A to C is two intervals.
• C = 1,500 + (2 × 500) = 1,500 + 1,000 = 2,500
• Or: C = D − 500 = 3,000 − 500 = 2,500

(c) 4,000 [2 marks]

• Distance D to E = 2 × 500 = 1,000 [1 mark]
• E = 3,000 + 1,000 = 4,000 [1 mark]

32. [5 marks]

(a) 4,745 toys [2 marks]

• Second week: 3,456 + 1,289 [1 mark]
• 3,456 + 1,289 = 4,745 toys [1 mark]

(b) 3,758 toys [1 mark]

• Third week: 4,745 − 987 = 3,758 toys

(c) 11,959 toys [2 marks]

• Total: 3,456 + 4,745 + 3,758 [1 mark]
• 3,456 + 4,745 = 8,201
• 8,201 + 3,758 = 11,959 toys [1 mark]

33. [5 marks]

Generated table for 33.

(a) $69 [2 marks]

• Bag: $45
• Two storybooks: 2 × $12 =$24 [1 mark for storybooks]
• Total: $45 +$24 = $69 [1 mark]

(b) $67 [2 marks]

• Calculator: $25
• Stationery set: $8
• Total spent: $25 +$8 = $33 [1 mark]
• Change: $100 −$33 = $67 [1 mark]

(c) 3 storybooks [1 mark]

• Water bottle: $15
• Remaining: $50 −$15 = $35
• Storybooks at $12 each:$35 ÷ $12 = 2 remainder$11
• She can buy 3 storybooks? Let me recheck: 3 × $12 =$36, but $35 <$36.
• Actually: 2 × $12 =$24, $24 ≤$35. 3 × $12 =$36 > $35.
• Answer: 2 storybooks

Wait, let me re-read: "one water bottle and as many storybooks as she can with $50"

After water bottle ($15):$35 left. $35 ÷$12 = 2 remainder 11, so 2 storybooks.

Answer: 2 storybooks

34. [5 marks]

(a) 3,734 children [2 marks]

• Children = adults + 1,278 [1 mark]
• 2,456 + 1,278 = 3,734 children [1 mark]
• Working: 2,456 + 1,278:
  • 6 + 8 = 14, write 4, carry 1
  • 5 + 7 + 1 = 13, write 3, carry 1
  • 4 + 2 + 1 = 7
  • 2 + 1 = 3

(b) 467 rows [2 marks]

• 3,734 ÷ 8 [1 mark]
• 3,734 ÷ 8 = 466 remainder 6
• Need 467 rows (466 full rows + 1 more row for remaining 6 children)
• Or: 466 × 8 = 3,728; 3,734 − 3,728 = 6; need 467 rows.
• Answer: 467 rows [1 mark]

(c) $117,400 [1 mark]

• Adults: 2,456 × $25 =$61,400
• Children: 3,734 × $15 =$56,010
• Total: $61,400 +$56,010 = $117,410

Let me recheck: 2,456 × $25:

• 2,456 × 20 = 49,120
• 2,456 × 5 = 12,280
• Total: 61,400 ✓

3,734 × $15:

• 3,734 × 10 = 37,340
• 3,734 × 5 = 18,670
• Total: 56,010 ✓

$61,400 +$56,010 = $117,410

35. [5 marks]

Generated diagram for 35.

(a) 7,520 [1 mark]

• Largest: place biggest digit in highest place value.
• Thousands: 7, Hundreds: 5, Tens: 2, Ones: 0.

(b) 2,057 [1 mark]

• Smallest 4-digit number (can't start with 0): thousands must be 2.
• Then 0, 5, 7 in remaining places: 2,057.

(c) 5,463 [1 mark]

• 7,520 − 2,057 = 5,463

(d) 5,027 and 5,072 [2 marks]

• Rounds to 5,000 (nearest thousand): number must be from 4,500 to 5,499.
• With digits 7, 0, 5, 2: thousands digit must be 5 to be in range.
• Possible numbers: 5,027; 5,072; 5,207; 5,270; 5,702; 5,720
• Check which round to 5,000:
  • 5,027 → 5,000 ✓
  • 5,072 → 5,000 ✓
  • 5,207 → 5,000 ✓
  • 5,270 → 5,000 ✓
  • 5,702 → 6,000 ✗
  • 5,720 → 6,000 ✗

Answer: 5,027; 5,072; 5,207; 5,270 [2 marks, all correct]

Actually I need to recheck: 5,207 rounds to 5,000? 5,207, hundreds digit is 2, so yes, rounds down to 5,000.

All four numbers with thousands=5 and hundreds < 5 work.

END OF ANSWER KEY