5th Grade
Subtraction Mixed Numbers
by Monica Yuskaitis, M.A.Ed.
Copyright © 2006 by Monica Yuskaitis
1
Objective
• To be able to subtract mixed
numbers with regrouping.
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2
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3
To Subtract Mixed Numbers
with Regrouping.
1) Regroup by borrowing one
from the 5.
41
58
5
3
- 8
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4
To Subtract Mixed Numbers with
Regrouping.
2) Change the 1 to 8/8.
41
58
5
3
- 8
8
8
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5
To Subtract Mixed Numbers
with Regrouping.
3) Add the 1/8 plus the 8/8.
41 8 9
58 +8 = 8
5
3
- 8
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6
To Subtract Mixed Numbers with
Regrouping.
4) Subtract the fractions.
41 8 9
58 +8 = 8
5
3
- 8
4
8
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7
To Subtract Mixed Numbers
with Regrouping.
5) Subtract the whole numbers.
41 8 9
58 +8 = 8
5
3
- 8
4
1
8
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8
To Subtract Mixed
Numbers with Regrouping.
6) Simplify your fraction.
41 8 9
58 +8 = 8
5
3
- 8
4
4
1
1 ÷
=
1
8
4
2
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Now you can do it!
2-4 7
=6 9
7
9 9
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Subtract.
4
3
5 9
7
2
- 9
Regroup by
borrowing 1
from the 5.
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11
Subtract.
4
3
5 9
7
2
- 9
9
9
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Change
the 1 to
9/9.
12
Subtract.
4
3
9
12
5 9 +9 = 9
7
2
- 9
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Add 3/9 +
9/9.
13
Subtract.
4
3
9
12
5 9 +9 = 9
7
2
- 9
Subtract
12/9 – 7/9.
5
9
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14
Subtract.
4
3
9
12
5 9 +9 = 9
7
2
- 9
Subtract
4 – 2.
5
2
9
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15
Subtract.
5
1
6 5
4
1
- 5
Regroup by
borrowing 1
from the 6.
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16
Subtract.
5
1
6 5
4
1
- 5
5
5
Change
the 1 to
5/5.
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Subtract.
5
1
5
6
6 5 +5 = 5
4
1
- 5
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Add 1/5 +
5/5.
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Subtract.
5
1
5
6
6 5 +5 = 5
4
1
- 5
Subtract
6/5 – 4/5.
2
5
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19
Subtract.
5
1
5
6
6 5 +5 = 5
4
1
- 5
2
4
5
Subtract
5 – 1.
Answer
4 2/5
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20
Objective
• To be able to subtract mixed
numbers with unlike
denominators with
regrouping.
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21
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22
To Subtract Mixed Numbers
with Regrouping.
1) Find the LCD or LCM of the
denominators.
1
58
3
3
- 4
8
8
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23
To Subtract Mixed Numbers
with Regrouping.
2) Find the equivalent fractions
with 8 as a denominator.
1
58
3
3
- 4
x1= 1
x1 8
x2= 6
x2 8
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24
To Subtract Mixed Numbers
with Regrouping.
3) Regroup by borrowing one
from the 5.
41
1
58 = 8
3
6
3
=
- 4
8
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25
To Subtract Mixed Numbers
with Regrouping.
4) Change the 1 to 8/8.
41
1
58 = 8
3
6
3
=
- 4
8
8
8
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26
To Subtract Mixed Numbers
with Regrouping.
5) Add the 1/8 and 8/8 together.
41
1
8
9
58 = 8 + 8 = 8
3
6
3
=
- 4
8
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27
To Subtract Mixed Numbers
with Regrouping.
6) Subtract the fractions.
41
58 =
3
3
=
- 4
3
8
1 + 8 = 9
8
8
8
6
8
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28
To Subtract Mixed Numbers
with Regrouping.
7) Subtract the whole numbers.
41
58 =
3
3
=
- 4
3
1
8
1 + 8 = 9
8
8
8
6
8
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Get your white boards out!
5
1-7
=4 9
5
3 9
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30
Subtract.
3
5 9
2
2
- 3
9
9
Use the short
cut to find the
least common
denominator.
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31
Subtract.
3
1
3
5 9x1 =9
2
3
6
x
2
=
- 3 3 9
Find the
equivalent
fractions with
9 as a
denominator.
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32
Subtract.
4
3
1
3
5 9x1 =9
2
3
6
x
2
=
- 3 3 9
Regroup by
borrowing 1
from the 5.
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33
Subtract.
4
3
3
5 9=9
2
6
=
2
- 3 9
9
9
Change the
1 to a fraction
with 9 as a
denominator.
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34
Subtract.
4
3
3
9
12
5 9=9 +9= 9
2
6
=
2
- 3 9
Add 3/9 + 9/9.
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35
Subtract.
4
3
3
9
12
5 9=9 +9= 9
2
6
=
2
Subtract
12/9
- 3 9
minus 6/9.
6
9
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36
Subtract.
4
3
3
9
12
5 9=9 +9= 9
2
6
=
2
Subtract
4
- 3 9
minus 2.
6
2
9
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37
Subtract.
4
3
3
9
12
5 9=9 +9= 9
2
6
Simplify
your
=
2
- 3 9
fraction.
6
3
2
÷ =
2
9
3 3
Copyright © 2006 by Monica Yuskaitis
38
Subtract.
4
3
3
9
12
5 9=9 +9= 9
2
6
Your
answer
=
2
- 3 9
is 2 2/3.
6
3
2
÷ =
2
9
3 3
Copyright © 2006 by Monica Yuskaitis
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Copyright Notice
• This software is copyrighted. The software
may not be copied, reproduced, translated
or reduced to any electronic medium
without the prior written consent of Monica
Yuskaitis (monismath@juno.com).
However, after you purchase it you may
download it in your classroom to use for
presentation purposes.
Copyright © 2006 by Monica Yuskaitis
40
Credits
Clipart from clipart.com
Written by Monica Yuskaitis
For Further Information
About this product or other
Monica’s Math presentations
Contact:
monismath@juno.com
Copyright © 2006 by Monica Yuskaitis
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