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# Subtracting fractions with unlike denominators

To subtract fractions with different denominators, you need to find a common denominator. This can be done by identifying the least common multiple of the two denominators. After rewriting the fractions so they both have the common denominator, you can subtract the numerators as you would with any two fractions.

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• what if they are the same denominaters
• If the denominators are the same , you leave the denominators the same and add or subtract the numerators. Make sure you don't add or subtract the denominators.
• What do i do when i have this?
14/6
The numerator is bigger than the denominator.
• The answer would be 2 2/6 because 6 goes into 14 2 times and 2 would be left and that turns into the numerator, and the denominator would stay the same
• how do you subtract 8/2 - 7/12
• create common denominators so set 8/2 to 48/12 (6 x 2=12, 8 x 6=48) then subtract 48 by 7 to get 41 and place that back over 12 to get 41/12
• how do you multiply or divide with unlike denominators
• what if there is 2 diffrent denomanonater
• You will have to find a multiple that both denominators have. Then, multiply the numerator by the number you multiplied the denominator to get the common multiple.

For example: 5/9 - 6/5
You will need to find a common multiple that 9 and 5 both have.

9: 9, 18, 27, 36, 45, 54...
5: 5, 10, 15, 20, 25, 30, 35, 45, 50...

In this case 45 is the common multiple. Then, you would have to multiply the numerators by the number you multiplied their denominator to get the common multiple. Since 9 times 5 equals 45, the 5 in 5/9 needs to be multiplied by 5 and the 6 in 6/5 would need to be multiplied by 9.

So, 5/9 becomes 25/45 and 6/5 becomes 54/45.

Therefore, 25/45 - 54/45 = -29/45

Hope this helped :)
• what if there numerators are bigger than there denominators
• then you turn the fraction into a mixed number
• I was given the question 2/x+4=3/x
I'm not sure how to work this out... how wold i make the denominates common?
• Your denominator would be either x or what x stands for.
(1 vote)
• how do I subtract mixed fraction where only one fraction is mixed
• You turn both fractions into improper fractions, next you find a like denominator, then you subtract.
• what if the numerater is bigger than the denominator