Fractions Subtraction: Simple Fractions, Common Denominator
On this page and the next page, we will subtract fractions that already have a common denominator.
To subtract two fractions, we:
1) Make sure that each fraction has the same denominator: the least common denominator.
2) Subtract only the top part (numerator) of each fraction.
3) After subtracting, write the answer over the denominator.
Our first example is 3 / 5 - 1 / 5:
1) Each fraction has the same denominator: 5.
2) 3 - 1 = 2.
3) 2 over 5 is 2/5. That wasn't hard, was it?
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The next example is 5 / 9 - 4 / 9:
1) Each fraction has the same denominator: 9.
2) 5 - 4 = 1.
3) 1 over 9 is 1 / 9.
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