Subtraction shortcuts

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Subtraction Shortcuts and Tips By Monica Yuskaitis

Transcript of Subtraction shortcuts

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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