Introduction to Negative Numbers

Hello, Year 6! Today, we are going to explore adding with negative numbers. You might have seen negative numbers before, especially when talking about temperatures or money. Let’s break it down step by step!

What are Negative Numbers?

Negative numbers are numbers less than zero. They can be written with a minus sign (-). For example:

  • -1, -2, -3, etc.

Adding with Negative Numbers

When we add a negative number, it’s like taking away from a number. Think of it this way:

  • If you have 5 apples and you give away 2 apples, how many do you have left?
  • You started with 5 (positive) and gave away 2 (negative), so you have 5 – 2 = 3 apples.

Key Rules for Adding with Negative Numbers

  1. Positive + Positive = PositiveExample: 3 + 2 = 5
  2. Negative + Negative = NegativeExample: -3 + (-2) = -5
  3. Positive + Negative = Depends on the Numbers
    • If the positive number is bigger:Example: 5 + (-2) = 3 (You have 5 and take away 2)
    • If the negative number is bigger:Example: -3 + 2 = -1 (You have -3 and add 2)

Visualising Adding with Negative Numbers

Imagine a number line:

  • Start at 0.
  • Move to the right for positive numbers.
  • Move to the left for negative numbers.

Example on a Number Line

  1. Start at 4.
  2. Add -3 (which means move left 3 spaces):4 → 3 → 2 → 1 → 0.So, 4 + (-3) = 1.
  3. Start at -2.
  4. Add 5 (move right 5 spaces):-2 → -1 → 0 → 1 → 2 → 3.So, -2 + 5 = 3.

Tips and Tricks

  • Think of negative numbers as ‘taking away’.
  • Use a number line to help you visualise.
  • Remember that two negatives make a positive when you are adding!

Practice Questions

Easy Level Questions

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

Medium Level Questions

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

Hard Level Questions

  1. 14 + (-9)
  2. -15 + 6
  3. -12 + 8
  4. 7 + (-14)
  5. -10 + (-5)
  6. 0 + (-15)
  7. 13 + (-18)
  8. -13 + 7
  9. 16 + (-20)
  10. -11 + 4
  11. -5 + (-10)
  12. -20 + 5
  13. 19 + (-24)
  14. -18 + 9
  15. -25 + 10
  16. 22 + (-30)
  17. -17 + 15
  18. -6 + (-12)
  19. -23 + 8
  20. 30 + (-50)

Answers and Explanations

Easy Level Answers

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

Medium Level Answers

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

Hard Level Answers

  1. 14 + (-9) = 5
  2. -15 + 6 = -9
  3. -12 + 8 = -4
  4. 7 + (-14) = -7
  5. -10 + (-5) = -15
  6. 0 + (-15) = -15
  7. 13 + (-18) = -5
  8. -13 + 7 = -6
  9. 16 + (-20) = -4
  10. -11 + 4 = -7
  11. -5 + (-10) = -15
  12. -20 + 5 = -15
  13. 19 + (-24) = -5
  14. -18 + 9 = -9
  15. -25 + 10 = -15
  16. 22 + (-30) = -8
  17. -17 + 15 = -2
  18. -6 + (-12) = -18
  19. -23 + 8 = -15
  20. 30 + (-50) = -20

I hope this helps you understand how to add negative numbers! Remember, practice makes perfect, so keep working on those questions!