It means finding the lowest common denominator.
So if your fraction is 10/32 (ten over thirty-two) you can reduce this by dividing the top and bottom by two. You'll get 5/16 (five over sixteen). There are no other numbers that you can evenly divide the top and bottom numbers by, so you have successfully reduced this fraction.
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In order to find the LCD when adding or subtracting fractions
The HCF helps when reducing fractions. The LCM helps when adding or subtracting fractions.
Factor :D
By reducing them to their lowest terms
If you mean 6/30 then it is 1/5 as a reduced fraction
They are useful in reducing fractions and to simplify radicals. They are useful in reducing fractions and to simplify radicals.
When you are reducing fractions.
Answers.com
In order to find the LCD when adding or subtracting fractions
reducing
Expanding fractions
The HCF helps when reducing fractions. The LCM helps when adding or subtracting fractions.
When reducing fractions to their lowest terms or finding the LCD of fractions
Factor :D
When you are reducing fractions.
By reducing them to their lowest terms