Introduction to Subtraction with Borrowing

Hello, Year 4! Today, we’re going to learn about subtraction with borrowing. This is a special method we use when we need to subtract one number from another, and the number we are subtracting from is smaller in one of the columns.

What is Borrowing?

When we subtract, sometimes we need to borrow from the next column to help us. Think of it like asking a friend for a pencil when you don’t have one!

Steps to Subtraction with Borrowing

Let’s break it down step-by-step:

  1. Write the Numbers: Place the numbers one under the other, aligning them by place value (units, tens, hundreds).
  2. Start from the Right: Begin subtracting from the units column (the rightmost column).
  3. Check If You Can Subtract: If the top number (the minuend) is smaller than the bottom number (the subtrahend), you need to borrow from the next column.
  4. Borrow:
    • Cross out the number in the next column to the left.
    • Decrease it by 1.
    • Add 10 to the current column (where you’re subtracting).
  5. Subtract: Now, you can subtract the numbers in that column.
  6. Move Left: Repeat the process for the next columns until you have subtracted all the way to the left.

Example

Let’s look at an example:

Example 1:

Subtract 54 from 132.

    1 3 2  (132) -     5 4  (54) -----------
  1. Start from the right: 2 – 4. We can’t do that because 2 is smaller than 4.
  2. Borrow from the 3 (the tens column). Change 3 to 2 and add 10 to the 2 (now it’s 12).
  3. Now we have:
    1 2  (the tens column becomes 2)    1 2 12  (12 in the units column) -     5 4 -----------
  1. Now, subtract: 12 – 4 = 8.
  2. Move to the tens: 2 – 5. We can’t do that. Borrow again! Change 1 (the hundreds column) to 0 and add 10 to the 2 (now it’s 12).
    0 2  (the hundreds column becomes 0)    0 12  (the tens column is now 12)    1 2 12 -     5 4 -----------
  1. Now, subtract: 12 – 5 = 7.
  2. Finally, move to the hundreds: 0 – 0 = 0.

So, the answer is 78!

Key Rules

  • Always start subtracting from the rightmost column.
  • If the top number is smaller than the bottom number, you must borrow from the left column.
  • Remember to keep your numbers lined up by place value!

Tips and Tricks

  • Practice: The more you practice, the easier it gets!
  • Check Your Work: After you finish, you can add your answer to the number you subtracted to see if you get back to the original number.
  • Use a Number Line: Sometimes, drawing a number line can help you visualise the subtraction.

Practice Questions

Easy Level (20 Questions)

  1. 23 – 12 = ?
  2. 45 – 21 = ?
  3. 32 – 11 = ?
  4. 54 – 23 = ?
  5. 75 – 34 = ?
  6. 61 – 30 = ?
  7. 84 – 42 = ?
  8. 91 – 50 = ?
  9. 72 – 61 = ?
  10. 58 – 37 = ?
  11. 44 – 22 = ?
  12. 80 – 39 = ?
  13. 39 – 18 = ?
  14. 67 – 25 = ?
  15. 53 – 32 = ?
  16. 66 – 15 = ?
  17. 70 – 44 = ?
  18. 88 – 26 = ?
  19. 20 – 19 = ?
  20. 60 – 33 = ?

Medium Level (20 Questions)

  1. 123 – 47 = ?
  2. 154 – 76 = ?
  3. 231 – 59 = ?
  4. 302 – 184 = ?
  5. 465 – 298 = ?
  6. 250 – 139 = ?
  7. 410 – 275 = ?
  8. 543 – 228 = ?
  9. 632 – 495 = ?
  10. 785 – 374 = ?
  11. 840 – 357 = ?
  12. 912 – 578 = ?
  13. 765 – 289 = ?
  14. 894 – 467 = ?
  15. 432 – 215 = ?
  16. 678 – 349 = ?
  17. 850 – 466 = ?
  18. 900 – 584 = ?
  19. 732 – 489 = ?
  20. 850 – 435 = ?

Hard Level (20 Questions)

  1. 1002 – 478 = ?
  2. 1350 – 679 = ?
  3. 1420 – 578 = ?
  4. 2563 – 829 = ?
  5. 3500 – 1967 = ?
  6. 4050 – 2398 = ?
  7. 4802 – 2654 = ?
  8. 5230 – 4801 = ?
  9. 6120 – 2948 = ?
  10. 7490 – 3587 = ?
  11. 8301 – 5124 = ?
  12. 9000 – 7623 = ?
  13. 10000 – 5489 = ?
  14. 12000 – 7865 = ?
  15. 13500 – 8423 = ?
  16. 15000 – 9130 = ?
  17. 16200 – 7534 = ?
  18. 17500 – 9642 = ?
  19. 18000 – 12789 = ?
  20. 20000 – 13457 = ?

Answers

Easy Level Answers

  1. 11
  2. 24
  3. 21
  4. 31
  5. 41
  6. 31
  7. 42
  8. 41
  9. 11
  10. 21
  11. 22
  12. 41
  13. 21
  14. 42
  15. 21
  16. 51
  17. 26
  18. 62
  19. 1
  20. 27

Medium Level Answers

  1. 76
  2. 78
  3. 172
  4. 118
  5. 167
  6. 111
  7. 135
  8. 315
  9. 137
  10. 411
  11. 483
  12. 334
  13. 476
  14. 483
  15. 217
  16. 329
  17. 384
  18. 316
  19. 243
  20. 415

Hard Level Answers

  1. 524
  2. 671
  3. 842
  4. 1734
  5. 1533
  6. 1652
  7. 1148
  8. 429
  9. 3172
  10. 3903
  11. 3177
  12. 1377
  13. 4511
  14. 4135
  15. 5077
  16. 5860
  17. 8666
  18. 7858
  19. 653
  20. 6543

Happy subtracting, everyone! Keep practising, and you’ll become experts in subtraction with borrowing!