The previous chapter Fractions Types, Representation With Diagrams And Conversions discusses what a fraction is and what the various types of fractions are. This chapter will explore the methods with examples to do the arithmetic operations like addition, subtraction, multiplication and division on fractions.
Addition of fractions
With same denominators (Like fractions)
To add like fractions, only numerators are added and keep the value of denominator as it is.
Add and
As the denominator is 8 and add numerator of both fractions only
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Add
Here, the denominator is 4 for all fractions, so add numerators of all fractions only.
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With different denominators (Unlike fractions)
To add unlike fractions, convert unlike fractions into like fractions by taking LCM of their denominators.
Add
Step 1: Take LCM of denominators of fractions and

Step 2: Multiply both fractions numerator and denominators by the same numbers such that the denominators become equal to LCM 12.
Step 3: Add the like fractions and
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∴
Add
Step 1: Take LCM of denominators of fractions and

Step 2: Multiply numerators and denominators of all fractions by the same numbers such that their denominators become equal to LCM 12.
Step 3: Add the like fractions and
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∴
Subtraction of fractions
With same denominator (Like fractions)
In subtraction of like fractions, only numerators are subtracted and the values of the denominator do not change.
Subtract from
As these are like fractions with their same denominators of 9.
So, subtract numerator of both fractions only.
Subtract from
Here, the two fractions are like fractions and their denominator is 12.
So, subtract numerators of both fractions only.
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With different denominators (Unlike fractions)
To subtract the unlike fractions, convert unlike fractions into like fractions by taking LCM of their denominators.
Subtract from
Step 1: Take LCM of denominators of fractions.

LCM of 4 and 3 is 12
Step 2: Convert unlike fractions into like fractions by multiplying a number which makes denominators equal to LCM 12.
Step 3: Subtract from
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∴
Multiplication of fractions
With whole number
To multiply a fraction with the whole number, multiply only the numerator by the given whole number and keep the denominator same. Then reduce it to its lowest term.
Here, is a fraction and 2 is a whole number.
2 is written as
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A fraction by fraction
To multiply a fraction by another fraction, multiply their corresponding numerators and denominators. Then reduce the obtained fraction into its lowest form.
Multiply fraction by
Here, multiply numerators 7 and 3. Also, multiply their denominators 5 and 4.
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Multiply fractions
multiply numerators 2, 4 and 3 and also multiply denominators 5, 6 and 2.
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Now should be reduced to its lowest term by dividing with the common factor 12.
Division of fractions
To divide a fraction with another fraction, first the division is changed into multiplication by changing the division sign into multiplication and taking reciprocal of the second fraction.
Divide by
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Divide fraction by whole number 6
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should be reduced into its the lowest term by dividing with common factor 2
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Divide 5 by
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