Mental MathMental MathMental MathMental MathDigit by Digit Addition and Digit by Digit Addition and

SubtractionSubtraction

Add in Your Head

13 62 75

1 6 7I n your head add:

If there are no carries, use digit by digit addition

3 2

7

1 6

6

75

1I n your head add:

If there are no carries, use digit by digit addition

Add in Your Head

3 21 6 7

6 7

5

1I n your head add:

If there are no carries, use digit by digit addition

Add in Your Head

3 2

5

1 6

2

75

3I n your head add:

If there are no carries, use digit by digit addition

Add in Your Head

3 2

5

1 6

2

75

3I n your head add:

If there are no carries, use digit by digit addition

Add in Your Head

If there are no carries, use digit by digit addition

Add in Your Head

13 62 75

Done!

7598

1 6

137 2

7

5 62 3

I n your head add:

If there are no carries, use digit by digit addition

Any Number of Digits

1 6

1 6

7598375 223

7I n your head add:

If there are no carries, use digit by digit addition

Any Number of Digits

1 6 7

1 6

598375 223

7I n your head add:

If there are no carries, use digit by digit addition

Any Number of Digits

3 2

3 2

591 75 6 2

5

3 87

I n your head add:

If there are no carries, use digit by digit addition

Any Number of Digits

3 2 5

3 2

91 75 6 23

5

87

I n your head add:

If there are no carries, use digit by digit addition

Any Number of Digits

7 2

7 2

13 5 62 3 7598

9I n your head add:

If there are no carries, use digit by digit addition

Any Number of Digits

7 2 9

7 2

13 8

9

5 62 3 75

I n your head add:

If there are no carries, use digit by digit addition

Any Number of Digits

5 3

5 3

137 622 7598

8I n your head add:

If there are no carries, use digit by digit addition

Any Number of Digits

5 3 8

5 3

137 622 759

8I n your head add:

If there are no carries, use digit by digit addition

Any Number of Digits

1375 6223 7598

Done!

If there are no carries, use digit by digit addition

Any Number of Digits

Subtract In Your Head

83 262 1

If there are no carries, use digit by digit subtraction

8 6

8 6

2 75

7

3

I n your head subtract:

If there are no carries, use digit by digit subtraction

Subtract In Your Head

8 6 2

8 6

2

2

53

I n your head subtract:

If there are no carries, use digit by digit subtraction

Subtract In Your Head

3 2

3 2

8 6 25

1I n your head subtract:

If there are no carries, use digit by digit subtraction

Subtract In Your Head

3 2 1

3 2

8 6 2

1I n your head subtract:

If there are no carries, use digit by digit subtraction

Subtract In Your Head

83 62 21

Done!

If there are no carries, use digit by digit subtraction

Subtract In Your Head

8375 622 53 21 2

If there are no carries, use digit by digit subtraction

Any Number of Digits

75937 8

7

238

8 6

5 62

I n your head subtract:

If there are no carries, use digit by digit subtraction

Any Number of Digits

58 6 2

8

987 3

6

3 5 2

2

2

I n your head subtract:

If there are no carries, use digit by digit subtraction

Any Number of Digits

53 2

3

988 75 6 23 2

12I n your head subtract:

If there are no carries, use digit by digit subtraction

Any Number of Digits

3 2 198

3 2 1

8 75 6 23 2

I n your head subtract:

If there are no carries, use digit by digit subtraction

Any Number of Digits

83 5 62 3 217

2 17

982

I n your head subtract:

If there are no carries, use digit by digit subtraction

Any Number of Digits

83 5 62 3 217 5

7 2 5

82

I n your head subtract:

If there are no carries, use digit by digit subtraction

Any Number of Digits

8375 6223 21

7 5

58

2I n your head subtract:

If there are no carries, use digit by digit subtraction

Any Number of Digits

837 622 215

3 25

583

I n your head subtract:

If there are no carries, use digit by digit subtraction

Any Number of Digits

837 622 215

5 3 2

53 2

I n your head subtract:

If there are no carries, use digit by digit subtraction

Any Number of Digits

8375 6223 2152

Done!

If there are no carries, use digit by digit subtraction

Any Number of Digits

Work it out!

24 533 5

Work it out!

24 33 55

Work it out!

68 427 1

Work it out!

68 27 41

Work it out!

6,092 3,0 351 ,041

Work it out!

6,092 3,051 3,041

Work it out!

12,345 54,3 661 62 ,66

Work it out!

12,345 54,321 66,666

Work it out!

15.03 34. 474 9.77

Work it out!

15.03 34.74 49.77

Work it out!

0.0396 0.02 0.4 27 012

Work it out!

0.0396 0.0274 0.0122