Counting Up To Subtract

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How to subtract by adding on, using a column method

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Counting Up To Subtract

  1. 1. Subtraction of Whole Numbers by Counting Up, Using A Column Method (the 2nd step towards using a standard written method for subtraction) For more maths help & free games related to this, visit: www.makemymathsbetter.com
  2. 2. To “Count Up” you need to add on from the smaller number to the larger number in stages. To record it using a column method you need to first be able to record it on a number line. For example 86 – 47 = 39: +3 47 50 + 30 +6 56 86
  3. 3. To “Count Up” you need to add on from the smaller number to the larger number in stages. To record it using a column method you need to first be able to record it on a number line. For example 86 – 47 = 39: +3 47 50 This can then be developed into a column method: + 30 +6 86 56 86 -47
  4. 4. To “Count Up” you need to add on from the smaller number to the larger number in stages. To record it using a column method you need to first be able to record it on a number line. For example 86 – 47 = 39: +3 47 50 This can then be developed into a column method: + 30 +6 86 56 86 -47 3 50
  5. 5. To “Count Up” you need to add on from the smaller number to the larger number in stages. To record it using a column method you need to first be able to record it on a number line. For example 86 – 47 = 39: +3 47 50 This can then be developed into a column method: + 30 +6 86 56 86 -47 3 50 6 56
  6. 6. To “Count Up” you need to add on from the smaller number to the larger number in stages. To record it using a column method you need to first be able to record it on a number line. For example 86 – 47 = 39: +3 47 50 This can then be developed into a column method: + 30 +6 86 56 86 -47 3 50 6 30 56 86
  7. 7. To “Count Up” you need to add on from the smaller number to the larger number in stages. To record it using a column method you need to first be able to record it on a number line. For example 86 – 47 = 39: +3 47 50 This can then be developed into a column method: + 30 +6 86 56 86 -47 3 50 6 30 56 86 39
  8. 8. As you become more confident, the number of steps can be reduced: 86 -47
  9. 9. As you become more confident, the number of steps can be reduced: 86 -47 9 56
  10. 10. As you become more confident, the number of steps can be reduced: 86 -47 9 56 30 86
  11. 11. As you become more confident, the number of steps can be reduced: 86 -47 9 56 30 86 39
  12. 12. Counting up can also be used with 3 digit numbers, for example: 335 – 177 = 158. Firstly, using a number line: +3 177 180 + 20 + 30 + 100 200 300 330 335 +5 330 335
  13. 13. Counting up can also be used with 3 digit numbers, for example: 335 – 177 = 158. Firstly, using a number line: +3 177 180 + 20 + 30 + 100 200 Then using the column method: 300 335 -177 +5 330 335
  14. 14. Counting up can also be used with 3 digit numbers, for example: 335 – 177 = 158. Firstly, using a number line: +3 177 180 + 20 + 30 + 100 200 Then using the column method: 300 335 -177 3 180 +5 330 335
  15. 15. Counting up can also be used with 3 digit numbers, for example: 335 – 177 = 158. Firstly, using a number line: +3 177 180 + 20 + 30 + 100 200 Then using the column method: 300 335 -177 3 20 180 200 +5 330 335
  16. 16. Counting up can also be used with 3 digit numbers, for example: 335 – 177 = 158. Firstly, using a number line: +3 177 180 + 20 + 30 + 100 200 Then using the column method: 300 335 -177 3 20 100 180 200 300 +5 330 335
  17. 17. Counting up can also be used with 3 digit numbers, for example: 335 – 177 = 158. Firstly, using a number line: +3 177 180 + 20 + 30 + 100 200 Then using the column method: 300 335 -177 3 20 100 30 180 200 300 330 +5 330 335
  18. 18. Counting up can also be used with 3 digit numbers, for example: 335 – 177 = 158. Firstly, using a number line: +3 177 180 + 20 + 30 + 100 200 Then using the column method: 300 335 -177 3 20 100 30 5 180 200 300 330 335 +5 330 335
  19. 19. Counting up can also be used with 3 digit numbers, for example: 335 – 177 = 158. Firstly, using a number line: +3 177 180 + 20 + 30 + 100 200 Then using the column method: 300 335 -177 3 20 100 30 5 158 180 200 300 330 335 +5 330 335
  20. 20. As with 2 digit numbers, the amount of steps can be reduced: 335 -177
  21. 21. As with 2 digit numbers, the amount of steps can be reduced: 335 -177 23 200
  22. 22. As with 2 digit numbers, the amount of steps can be reduced: 335 -177 23 135 200 335
  23. 23. As with 2 digit numbers, the amount of steps can be reduced: 335 -177 23 135 158 200 335
  24. 24. That’s it for now...... For more help with your maths, try my book: mastering multiplication tables on amazon.com

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