Primary 5 Mathematics Semestral Assessment 2 (End of Year) Paper 2

TuitionGoWhere Practice Paper — Mathematics Primary 5

SA2 Practice Paper — Version 2 of 5: Answer Key

Section A: Multiple Choice (10 marks)

1. D — 700,000

The digit 7 is in the hundred thousands place. 7 × 100,000 = 700,000. [1]

2. A — 6,402,015

6,000,000 + 402,000 + 15 = 6,402,015. [1]

3. C — 4,900,000

The hundred thousands digit is 8. The ten thousands digit is 7 (≥ 5), so round up: 4,876,352 → 4,900,000. [1]

4. B — 5,000

5,000,000 ÷ 1,000 = 5,000 (remove 3 zeros). [1]

5. B — 1,034,578

Arrange digits in ascending order: 0, 1, 3, 4, 5, 7, 8. The first digit cannot be 0, so the smallest number is 1,034,578. [1]

6. B — 2,440,500

2,340,500 + 100,000 = 2,440,500. [1]

7. A — Eight million, ninety thousand, three hundred and six

8,000,000 + 90,000 + 300 + 6 = 8,090,306. [1]

8. A — 35,208

3 × 10,000 = 30,000; 5 × 1,000 = 5,000; 2 × 100 = 200; 8 × 1 = 8. Total = 30,000 + 5,000 + 200 + 8 = 35,208. [1]

9. B — 5,290,876

All numbers start with 5,2. Compare the thousands digit: 9 > 0, so B and D are candidates. Compare hundreds: 8 > 6, so B is greatest. [1]

10. A — 6 million

3,450,000 + 2,875,000 = 6,325,000. Rounded to nearest million: 6,000,000 (since 325,000 < 500,000). [1]

Section B: Short Answer (20 marks)

11. 4,612,953 [2]

Award 2 marks for the correct answer. Award 1 mark if the student writes a number with most place values correct but makes one digit error. Common mistake: Writing 4,612,593 (swapping tens and hundreds digits).

12. 6,023,451, 6,032,514, 6,203,415, 6,230,145 [2]

Compare digit by digit from the left. All start with 6. Compare hundred thousands: 0 < 2, so the first two are smaller. Between 6,023,451 and 6,032,514: ten thousands digit 2 < 3, so 6,023,451 is smallest. Similarly for the larger pair. Award 2 marks for all four in correct order. Award 1 mark if two or three are in correct relative position.

13. (a) 9,864,210 (b) 1,024,689 [2]

(a) Arrange digits in descending order: 9, 8, 6, 4, 2, 1, 0 → 9,864,210. (b) Arrange in ascending order: 0, 1, 2, 4, 6, 8, 9. First digit cannot be 0, so: 1,024,689. Award 1 mark for each correct answer.

14. 1,500,000 [2]

5,000,000 − 3,500,000 = 1,500,000. Award 2 marks for correct answer. Award 1 mark for correct method with arithmetic error.

15. (a) 7,645,000 (b) 7,654,999 [2]

Rounding to nearest ten thousand means the ten thousands digit is 5, and we look at the thousands digit. (a) Smallest: the thousands digit must be 5 (to round up to 5 in ten thousands), so 7,645,000. (b) Greatest: the thousands digit is 4 (rounds down, keeping 5 in ten thousands), and all lower digits are 9: 7,654,999. Award 1 mark for each correct answer. Common mistake: Writing 7,650,000 as the greatest — but any number from 7,650,001 to 7,654,999 also rounds to 7,650,000.

16. 4,380,000 [2]

4,380 × 1,000 = 4,380,000 (add 3 zeros). Award 2 marks for correct answer.

17. 81,000 [2]

8,100,000 ÷ 100 = 81,000 (remove 2 zeros). Award 2 marks for correct answer.

18. Ten thousands (or 80,000) [2]

2,487,635 — the digit 8 is in the ten thousands place. Its value is 80,000. Award 2 marks for correct answer. Accept "ten thousands" or "80,000".

19. 4,250,000 [2]

The pattern increases by 1,000,000 each time. 3,250,000 + 1,000,000 = 4,250,000. Award 2 marks for correct answer.

20. 5,420,500 [2]

1,340,500 + 2,080,750 + 1,999,250 = 5,420,500. Working: 1,340,500 + 2,080,750 = 3,421,250 3,421,250 + 1,999,250 = 5,420,500 Award 2 marks for correct answer with working. Award 1 mark for correct method with minor arithmetic error.

Section C: Structured / Problem Solving (20 marks)

21. (a) $10,000,000 (b)$2,000,000 [4]

(a) 2,350,000 + 1,780,000 + 3,120,000 + 2,750,000 = 4,130,000 + 3,120,000 + 2,750,000 = 7,250,000 + 2,750,000 = 10,000,000 (b) 12,000,000 − 10,000,000 = 2,000,000 Award 2 marks for each part. Award 1 mark per part for correct method with arithmetic error.

22. (a) Singapore: 6,000,000; Malaysia: 34,000,000 (b) 40,000,000 [4]

(a) 5,917,000 → nearest million: 6,000,000 (hundred thousands digit is 9, round up). 34,308,000 → nearest million: 34,000,000 (hundred thousands digit is 3, round down). (b) 6,000,000 + 34,000,000 = 40,000,000 Award 2 marks for (a) — 1 mark per correct rounding. Award 2 marks for (b).

23. (a) 4,700,030 (b) Four million, seven hundred thousand and thirty [4]

The number is between 4,000,000 and 5,000,000 → millions digit is 4. Hundred thousands digit is 7. Tens digit is 3. All other digits are 0. So: 4,700,030. In words: Four million, seven hundred thousand and thirty. Award 2 marks for each part. Award 1 mark per part if the student makes one place value error.

24. (a) Concert (b) 8,245,600; 8,100,000; 7,950,750; 7,890,350 (c) 355,250 [4]

(a) Compare all four numbers. 8,245,600 is the greatest → Concert. (b) Largest to smallest: 8,245,600 > 8,100,000 > 7,950,750 > 7,890,350. (c) 8,245,600 − 7,890,350 = 355,250. Award 1 mark for (a), 1 mark for (b), and 2 marks for (c) — 1 mark for correct method, 1 mark for correct answer.

25. (a) 4,076,250 (b) 3,398,750 [4]

(a) Items sold in Weeks 1 and 2: 1,230,500 + 2,845,750 = 4,076,250. (b) After Week 1: 6,500,000 − 1,230,500 = 5,269,500. After Week 2: 5,269,500 − 2,845,750 = 2,423,750. After Week 3 (received shipment): 2,423,750 + 975,000 = 3,398,750. Award 2 marks for each part. Award 1 mark per part for correct method with arithmetic error. Common mistake: Forgetting to add the Week 3 shipment in part (b).