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Subtraction Shortcutsand Tips
By Monica Yuskaitis
Subtracting Across Zeros
3 0 21 9 8
Step 1 – Borrow 1 from the 30
3 0 21 9 8
Step 2 – Cross out the 30
3 0 21 9 8
Step 3 – Write a 29 above the 30
3 0 21 9 8
2 9
Step 4 – Write a 1 in front of the 2
3 0 21 9 8
2 9
1
Step 5 – Subtract 8 from 12
3 0 21 9 8
2 9
1
4
Step 6 – Subtract 9 from 9
3 0 21 9 8
2 9
1
40
Step 7 – Subtract 1 from 2
3 0 21 9 8
2 9
1
401
We’re Finished
3 0 21 9 8
2 9
1
401
Second Example
8 0 0 23 7 6 5
Step 1 – Borrow 1 from 800
8 0 0 23 7 6 5
Step 2 – Cross out the 800
8 0 0 23 7 6 5
Step 3 – Write 799 above the 800
8 0 0 23 7 6 5
7 9 9
Step 4 – Write a 1 next to the 2
8 0 0 23 7 6 5
7 9 9
1
Step 5 – Subtract 5 from the 12
8 0 0 23 7 6 5
7 9 9
1
7
Step 6 – Subtract 6 from the 9
8 0 0 23 7 6 5
7 9 9
1
73
Step 7 – Subtract 6 from the 9
8 0 0 23 7 6 5
7 9 9
1
732
Step 7 – Subtract 3 from the 7
8 0 0 23 7 6 5
7 9 9
1
7324
We’re Finished
8 0 0 23 7 6 5
7 9 9
1
7324
It’s Your Turn
7 0 0 52 8 3 6
6 9 9
1
9614
It’s Your Turn Again
9 0 0 47 9 5 6
8 9 9
1
8401
Subtraction Tips
Never subtract the top number from the bottom number
4 6 6
6 1 32 7 9
Your answer will always be wrong.
Never borrow unless you need to
9 6 28 4 1
1
5
Your answer will always be wrong.
Practice your subtraction facts18 – 9 =18 – 7 =16 – 8 =14 – 8 =12 – 9 =11 – 3 =15 – 7 =9 – 3 =
18 – 5 =18 – 3 =16 – 7 =14 – 6 =12 – 4 =11 – 7 =15 – 6 =9 – 5 =
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