mixed numbers mixed numbers are whole numbers and fractions together. 1 2 3
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Mixed NumbersMixed Numbers
Mixed numbers are whole Mixed numbers are whole numbers and fractions numbers and fractions together.together.
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Subtracting Mixed NumbersSubtracting Mixed Numbers
• To subtract mixed numbers, you To subtract mixed numbers, you must make sure the fractions have must make sure the fractions have the same denominator, that’s the the same denominator, that’s the same bottom number. Find the same bottom number. Find the lowest common multiple of the two lowest common multiple of the two denominators. That is the number denominators. That is the number you will use for the denominator in you will use for the denominator in both fractions.both fractions.
Shortcut for Finding the Least Shortcut for Finding the Least Common Denominator or Least Common Denominator or Least
Common MultipleCommon Multiple
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Check to see if the smaller denominator divides evenly into the larger denominator.If it does, use the larger denominator for your LCD or LCM.
2 will divide evenly into 8, so 8 is your LCD or LCM.
3
1
To Subtract Mixed To Subtract Mixed Numbers With Unlike Numbers With Unlike
DenominatorsDenominators• Find the multiples of each Find the multiples of each
denominator.denominator.
1= 4, 8, 12, 16, 20, 24
1= 10, 20, 30, 40, 50-
4
10
3
1
To Subtract Mixed To Subtract Mixed Numbers With Unlike Numbers With Unlike
DenominatorsDenominators• Compare the lists of multiples. Compare the lists of multiples.
Circle the common multiples Circle the common multiples between the two lists.between the two lists.
1= 4, 8, 12, 16, 20, 24
1= 10, 20, 30, 40, 50+ 10
3
14
To Subtract Mixed To Subtract Mixed Numbers With Unlike Numbers With Unlike
DenominatorsDenominators
1= 4, 8, 12, 16, 20, 24
1= 10, 20, 30, 40, 50- 10
3
14
Use the least commonUse the least common
multiple as the multiple as the denominator.denominator.
To Subtract Mixed To Subtract Mixed Numbers With Unlike Numbers With Unlike
DenominatorsDenominators
1= 4, 8, 12, 16, 20, 24
1= 10, 20, 30, 40, 50- 10
3
14
This number is also calledThis number is also called
the least common the least common denominator.denominator.
To Subtract Mixed To Subtract Mixed Numberss With Unlike Numberss With Unlike
DenominatorsDenominators
1
1- 10
3
14 20
20
• Find the equivalent fractions for Find the equivalent fractions for 1/4 & 1/10 with 20 as the 1/4 & 1/10 with 20 as the denominator.denominator.
Ask yourself whatyou multiply 4 by
to get 20.x 5 =
To Subtract Mixed To Subtract Mixed Numbers With Unlike Numbers With Unlike
DenominatorsDenominators
1
1- 10
3
14 20
20
• Find the equivalent fractions for Find the equivalent fractions for 1/4 & 1/10 with 20 as the 1/4 & 1/10 with 20 as the denominator.denominator.
x 5 =
That’s right 5. Sinceyou are looking for
the equivalent fractionyou know the top
number must also bemultiplied by 5.
x 5 =
To Subtract Mixed To Subtract Mixed Numberss With Unlike Numberss With Unlike
DenominatorsDenominators
1
1- 10
3
14 20
20
• Find the equivalent fractions for Find the equivalent fractions for 1/4 & 1/10 with 20 as the 1/4 & 1/10 with 20 as the denominator.denominator.
x 5 =x 5 = To find the top number
just multiply 1 x 5 toget your equivalent
fraction.
5
To Subtract Mixed To Subtract Mixed Numbers With Unlike Numbers With Unlike
DenominatorsDenominators
1
1- 10
3
14 20
20
• Find the equivalent fractions for Find the equivalent fractions for 1/4 & 1/10 with 20 as the 1/4 & 1/10 with 20 as the denominator.denominator.
x 5 =x 5 = Now ask what you
multiply the 10 byto get 20.
5
x 2 =
To Subtract Mixed To Subtract Mixed Numbers With Unlike Numbers With Unlike
DenominatorsDenominators
1
1- 10
3
14 20
20
• Find the equivalent fractions for Find the equivalent fractions for 1/4 & 1/10 with 20 as the 1/4 & 1/10 with 20 as the denominator.denominator.
x 5 =x 5 = 5
x 2 =
That’s right 2. Since you are looking for the equivalent fraction you know the top number must also be multiplied by 2.
x 2 = 2
To Subtract Mixed To Subtract Mixed Numbers With Unlike Numbers With Unlike
DenominatorsDenominators
1
1- 10
3
1
4 20
20
• Now just subtract the Now just subtract the numerators.numerators.
x 5 =x 5 = 5
x 2 =Remember! We never subtract the denominators.
x 2 = 2
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To Subtract Mixed To Subtract Mixed Numbers With Unlike Numbers With Unlike
DenominatorsDenominators
1
1- 10
3
1
4 20
20
• Now subtract the whole Now subtract the whole numbers.numbers.
x 5 =x 5 = 5
x 2 =x 2 = 2
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Subtract These Mixed Subtract These Mixed NumbersNumbers
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Use the shortcut to find the
Least CommonDenominator
(LCD).
6
6
10
3
Subtract These Mixed Subtract These Mixed NumbersNumbers
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Now find theequivalent
fractions for1/3 & 1/6.
6
6x 1 =
x 2 =
Ask what do you multiply 3 by to get 6and what do you multiply 6 by to get 6.
10
3
Subtract These Mixed Subtract These Mixed NumbersNumbers
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Since you arewriting equivalent
fractions, nowmultiply the topnumbers by the
same number you did in the bottom.
6
6x 1 =
x 2 =x 1 =
x 2 =10
3
Subtract These Mixed Subtract These Mixed NumbersNumbers
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Now multiplyacross.
6
6x 1 =
x 2 =x 1 =
x 2 =
1
210
3
Subtract These Mixed Subtract These Mixed NumbersNumbers
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Subtract yournew
numerators.
6
6x 1 =
x 2 =x 1 =
x 2 =
1
2
16
3
10
Subtract These Mixed Subtract These Mixed NumbersNumbers
1316-
Subtract yourwhole
numbers.
6
6x 1 =
x 2 =x 1 =
x 2 =
1
2
16
3
10
7