Subraction
Look at the examples below before you attempt any of the exercises. It is important to understand how numbers are placed into units, tens, hundreds and thousands.
When you have done the exercises then check your answers.
Example 1
23 - 6 =?
- To take 3 away from 6 you will need to borrow from the tens column
- 13 - 6 = 7 enter 7 in the units column
- 1 - 0 = 1 enter 1 in the tens column
Th | H | T | U |
---|---|---|---|
12 | 13 | ||
6 | |||
1 | 7 | ||
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Example 2
223 - 18 = ?
- To take 3 away from 8 you will need to borrow from the tens column
- 13 - 8 = 5 enter 5 in the units column
- 1 - 1 = 0 enter 0 in the tens column
- 2 - 0 = 2 enter 2 in the hundreds column
Th | H | T | U |
---|---|---|---|
2 | 12 | 13 | |
1 | 8 | ||
2 | 0 | 5 | |
-
Example 3:
1262 - 125 = ?
- To take 2 away from 5 you will need to borrow from the tens column
- 12 - 5 = 7 enter 7 in the units column
- 5 - 2 = 3 enter 3 in the tens column
- 2 - 1 = 1 enter 1 in the hundreds column
- 1 - 0 = 1 enter 1 in the thousands column
Th | H | T | U |
---|---|---|---|
1 | 2 | 56 | 12 |
1 | 2 | 5 | |
1 | 1 | 3 | 7 |
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VIDEO
Have a look at the demonstration on the video to enhance your learning.
Adding numbers up in your head
It is more fun adding numbers up in your head!
Example 1:
43 - 22
- Take the large value 43 and subtract only the tens from the second value 22.
43 - 20 = 23 - From the value left over 23 subtract the units of the second value, which was 2.
23 - 2 = 21
Total= 21
Example 2:
265 - 139
- Subtract the hundereds 200 - 100 = 100
- Subtract 65 - 30 = 35
- Subtract 35 - 9 = 26
- Add 100 + 26
Total = 126