Primary 6 PSLE Mathematics Addition Subtraction Quiz

Primary 6 PSLE Mathematics Quiz - Addition Subtraction (Answer Key)

Total Marks: 40

Section A: Multiple Choice Questions (5 marks)

1. B) 378 134 [1 mark]

• Method: 245 678 + 132 456 = 378 134
• Teaching note: When adding large numbers, align the digits by place value (units, tens, hundreds, etc.) and add column by column, carrying over when the sum in a column is 10 or more.
• Common mistake: Forgetting to carry over the 1 from the thousands column.

2. A) 667 [1 mark]

• Method: 3 456 – 2 789 = 667
• Teaching note: "How many more" means subtraction. Subtract the smaller number from the larger number.
• Common mistake: Subtracting in the wrong order (2 789 – 3 456), which gives a negative number.

3. A) 499 999 [1 mark]

• Method: 500 000 – 1 = 499 999
• Teaching note: Subtracting 1 from a round number means decreasing the last non-zero digit by 1 and changing all zeros after it to 9s.
• Common mistake: Writing 499 900 or 499 990 by only changing the last digit.

4. A) 2 222 221 [1 mark]

• Method: 1 234 567 + 987 654 = 2 222 221
• Teaching note: Add carefully column by column. 7+4=11 (write 1, carry 1), 6+5+1=12 (write 2, carry 1), etc.
• Common mistake: Misaligning the digits when adding.

5. A) 4 543 211 [1 mark]

• Method: 8 000 000 – 3 456 789 = 4 543 211
• Teaching note: "Difference" means subtraction. When subtracting from a round number with many zeros, use borrowing across multiple columns.
• Common mistake: Forgetting to borrow correctly across the zeros.

Section B: Short Answer Questions (20 marks)

6. 15 678 + 8 456 = 24 134 books [2 marks]

• Method: Add the number of fiction and non-fiction books.
• Teaching note: "In total" means addition. Align the numbers by place value and add.
• Marking: 1 mark for correct working, 1 mark for correct answer.

7. $2 345 600 –$1 987 500 = $358 100 [2 marks]

• Method: Subtract the second half earnings from the first half earnings.
• Teaching note: "How much more" means subtraction. Subtract the smaller amount from the larger amount.
• Marking: 1 mark for correct working, 1 mark for correct answer.

8. 5 678 + 4 322 = 10 000 kg total; 10 000 – 6 500 = 3 500 kg left [2 marks]

• Method: First find the total harvest, then subtract the amount sold.
• Teaching note: This is a two-step problem. First add to find the total, then subtract to find what is left.
• Marking: 1 mark for correct total, 1 mark for correct final answer.

9. 1 234 – 1 198 = 36 more boys [2 marks]

• Method: Subtract the number of girls from the number of boys.
• Teaching note: "How many more" means subtraction. Compare the two numbers by subtracting the smaller from the larger.
• Marking: 1 mark for correct working, 1 mark for correct answer.

10. 3 456 + 2 789 + 4 567 = 10 812 bottles [2 marks]

• Method: Add the numbers for all three days.
• Teaching note: "Total" means addition. Add all three numbers together.
• Marking: 1 mark for correct working, 1 mark for correct answer.

11. 6 789 + 2 345 = 9 134 [2 marks]

• Method: Add 2 345 to 6 789.
• Teaching note: "More than" means addition. The number is 2 345 more than 6 789, so add 2 345 to 6 789.
• Marking: 1 mark for correct working, 1 mark for correct answer.

12. 5 000 – 2 345 = 2 655 women [2 marks]

• Method: Subtract the number of men from the total number of employees.
• Teaching note: "The rest" means subtraction. Find the number of women by subtracting the number of men from the total.
• Marking: 1 mark for correct working, 1 mark for correct answer.

13. 3 456 – 1 234 = 2 222 kg; 2 222 – 1 567 = 655 kg left [2 marks]

• Method: Subtract the amount unloaded at each stop from the original amount.
• Teaching note: This is a two-step subtraction problem. Subtract the first amount, then subtract the second amount from the result.
• Marking: 1 mark for correct working, 1 mark for correct answer.

14. 15 678 – 12 345 = 3 333 more toys [2 marks]

• Method: Subtract the January production from the February production.
• Teaching note: "How many more" means subtraction. Compare the two months by subtracting.
• Marking: 1 mark for correct working, 1 mark for correct answer.

15. 8 765 – 3 456 = 5 309; 5 309 + 1 234 = 6 543 chickens [2 marks]

• Method: First subtract the number sold, then add the number bought.
• Teaching note: This is a two-step problem. "Sold" means subtract, "bought" means add.
• Marking: 1 mark for correct working, 1 mark for correct answer.

Section C: Problem-Solving Questions (15 marks)

16. Term 3: 15 678 + 3 456 = 19 134 kg [3 marks] Total: 12 345 + 15 678 + 19 134 = 47 157 kg

• Method: First find the Term 3 amount by adding 3 456 to the Term 2 amount. Then add all three terms together.
• Teaching note: "More than" means addition. Find the Term 3 amount first, then add all three terms.
• Marking: 1 mark for correct Term 3 amount, 1 mark for correct total, 1 mark for correct final answer.

17. $123 456 +$98 765 = $222 221 spent** [3 marks] **$500 000 – $222 221 =$277 779 left

• Method: First find the total amount spent by adding the rent and salaries. Then subtract the total spent from the original amount.
• Teaching note: "How much was left" means subtraction. First add the expenses, then subtract from the original.
• Marking: 1 mark for correct total spent, 1 mark for correct subtraction, 1 mark for correct final answer.

18. 12 345 + 8 765 = 21 110 boxes received [3 marks] 25 000 + 21 110 = 46 110 boxes after receiving 46 110 – 15 000 = 31 110 boxes left

• Method: First add the boxes received on Monday and Tuesday. Then add that to the original amount. Finally, subtract the boxes sent out.
• Teaching note: "Received" means addition, "sent out" means subtraction. Do the additions first, then the subtraction.
• Marking: 1 mark for correct total received, 1 mark for correct intermediate total, 1 mark for correct final answer.

19. April: 5 678 + 1 234 = 6 912 packets [3 marks] Total: 3 456 + 4 567 + 5 678 + 6 912 = 20 613 packets

• Method: First find the April amount by adding 1 234 to the March amount. Then add all four months together.
• Teaching note: "More than" means addition. Find the April amount first, then add all four months.
• Marking: 1 mark for correct April amount, 1 mark for correct total, 1 mark for correct final answer.

20. 3 456 + 2 789 = 6 245 eggs sold [3 marks] 12 000 – 6 245 = 5 755 eggs after selling 5 755 + 1 500 = 7 255 eggs now

• Method: First find the total number of eggs sold. Subtract that from the original amount. Then add the eggs bought.
• Teaching note: "Sold" means subtraction, "bought" means addition. Find the total sold first, then subtract, then add.
• Marking: 1 mark for correct total sold, 1 mark for correct intermediate result, 1 mark for correct final answer.

End of Answer Key