Understanding Addition and Subtraction

Hello Year 6! Today, we are going to explore the important concepts of Addition and Subtraction. These are two of the most fundamental operations in maths that we use every day.

What is Addition?

Addition is the process of finding the total or sum by combining two or more numbers. For example, if you have 3 apples and you buy 2 more, you have:

3 + 2 = 5

So, 3 apples plus 2 apples equals 5 apples!

What is Subtraction?

Subtraction is the process of taking one number away from another. For example, if you have 5 apples and you give away 2, you are left with:

5 – 2 = 3

So, 5 apples minus 2 apples equals 3 apples!

Key Rules for Addition

  1. Order Doesn’t Matter: You can add numbers in any order. For example:2 + 3 = 5and3 + 2 = 5
  2. Zero Rule: Any number plus zero is that number. For example:7 + 0 = 7
  3. Grouping: You can group numbers in addition. For example:(2 + 3) + 4 = 9and2 + (3 + 4) = 9

Key Rules for Subtraction

  1. Order Matters: The order is very important in subtraction. For example:5 – 3 \neq 3 – 5
  2. Zero Rule: Any number minus zero is that number:9 – 0 = 9
  3. Subtracting from a Number: When you subtract a larger number from a smaller one, you get a negative number. For example:3 – 5 = -2

Tips and Tricks

  • Use Number Lines: A number line can help you visualize addition and subtraction. For addition, move to the right, and for subtraction, move to the left.
  • Break Down Bigger Numbers: For harder sums, break them down into smaller parts. For example:47 + 36 = (40 + 30) + (7 + 6) = 70 + 13 = 83
  • Check Your Work: After solving a problem, try to check your work by doing the opposite operation (e.g., if you added, try subtracting).

Practice Questions

Easy Level (20 Questions)

  1. What is (4 + 5)?
  2. What is (10 – 3)?
  3. What is (6 + 2)?
  4. What is (8 – 1)?
  5. What is (3 + 7)?
  6. What is (9 – 4)?
  7. What is (5 + 5)?
  8. What is (12 – 6)?
  9. What is (15 + 0)?
  10. What is (14 – 5)?
  11. What is (1 + 8)?
  12. What is (10 – 2)?
  13. What is (2 + 2)?
  14. What is (7 – 3)?
  15. What is (0 + 13)?
  16. What is (18 – 9)?
  17. What is (4 + 4)?
  18. What is (20 – 10)?
  19. What is (6 + 3)?
  20. What is (11 – 7)?

Medium Level (20 Questions)

  1. What is (25 + 15)?
  2. What is (50 – 23)?
  3. What is (32 + 18)?
  4. What is (60 – 45)?
  5. What is (27 + 33)?
  6. What is (99 – 54)?
  7. What is (45 + 27)?
  8. What is (80 – 29)?
  9. What is (13 + 39)?
  10. What is (70 – 26)?
  11. What is (31 + 19)?
  12. What is (58 – 32)?
  13. What is (22 + 24)?
  14. What is (90 – 15)?
  15. What is (44 + 56)?
  16. What is (75 – 50)?
  17. What is (36 + 14)?
  18. What is (100 – 37)?
  19. What is (25 + 25)?
  20. What is (88 – 44)?

Hard Level (20 Questions)

  1. What is (156 + 234)?
  2. What is (500 – 275)?
  3. What is (320 + 180)?
  4. What is (600 – 345)?
  5. What is (425 + 275)?
  6. What is (800 – 456)?
  7. What is (298 + 405)?
  8. What is (900 – 678)?
  9. What is (123 + 456)?
  10. What is (760 – 289)?
  11. What is (342 + 213)?
  12. What is (480 – 215)?
  13. What is (215 + 185)?
  14. What is (650 – 123)?
  15. What is (500 + 250)?
  16. What is (999 – 555)?
  17. What is (804 + 196)?
  18. What is (740 – 387)?
  19. What is (618 + 482)?
  20. What is (999 – 888)?

Answers and Explanations

Easy Level Answers

  1. 9
  2. 7
  3. 8
  4. 7
  5. 10
  6. 5
  7. 10
  8. 6
  9. 15
  10. 9
  11. 9
  12. 8
  13. 4
  14. 4
  15. 13
  16. 9
  17. 8
  18. 10
  19. 9
  20. 4

Medium Level Answers

  1. 40
  2. 27
  3. 50
  4. 15
  5. 60
  6. 45
  7. 72
  8. 51
  9. 52
  10. 44
  11. 50
  12. 26
  13. 46
  14. 75
  15. 100
  16. 25
  17. 50
  18. 63
  19. 50
  20. 44

Hard Level Answers

  1. 390
  2. 225
  3. 500
  4. 255
  5. 700
  6. 344
  7. 703
  8. 222
  9. 579
  10. 471
  11. 555
  12. 265
  13. 400
  14. 527
  15. 750
  16. 444
  17. 1000
  18. 353
  19. 1100
  20. 111

Great job, Year 6! Keep practicing your addition and subtraction skills, and remember to use the tips and tricks we discussed. Happy calculating!