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Subtract 1 from the top number in the column directly to the left.
Cross out the number you’re borrowing from, subtract 1, and write the answer above the number you crossed out.
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Add 10 to the top number in the column you were working in.
For example, suppose you want to subtract 386 – 94. The first step is to subtract 4 from 6 in the ones column, which gives you 2:
When you move to the tens column, however, you find that you need to subtract 8 – 9. Because 8 is smaller than 9, you need to borrow from the hundreds column. First, cross out the 3 and replace it with a 2, because 3 – 1 = 2:
Next, place a 1 in front of the 8, changing it to an 18, because 8 + 10 = 18:
Now you can subtract in the tens column: 18 – 9 = 9:
The final step is simple: 2 – 0 = 2:
Therefore, 386 – 94 = 292.
![image5.png](https://www.dummies.com/wp-content/uploads/215818.image5.png)
When borrowing from the next column isn’t an option, you need to borrow from the nearest non-zero column to the left.
In this example, the column you need to borrow from is the thousands column. First, cross out the 1 and replace it with a 0. Then place a 1 in front of the 0 in the hundreds column:
![image6.png](https://www.dummies.com/wp-content/uploads/215819.image6.png)
Now, cross out the 10 and replace it with a 9. Place a 1 in front of the 0 in the tens column:
![image7.png](https://www.dummies.com/wp-content/uploads/215820.image7.png)
Finally, cross out the 10 in the tens column and replace it with a 9. Then place a 1 in front of the 2:
![image8.png](https://www.dummies.com/wp-content/uploads/215821.image8.png)
At last, you can begin subtracting in the ones column: 12 – 8 = 4:
![image9.png](https://www.dummies.com/wp-content/uploads/215822.image9.png)
Then subtract in the tens column: 9 – 9 = 0:
![image10.png](https://www.dummies.com/wp-content/uploads/215823.image10.png)
Then subtract in the hundreds column: 9 – 3 = 6:
![image11.png](https://www.dummies.com/wp-content/uploads/215824.image11.png)
Because nothing is left in the thousands column, you don’t need to subtract anything else. Therefore, 1,002 – 398 = 604.