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The denominator tells you, in effect, what kind of fraction you have, whether it is halves, thirds, quarters, fifths, sixths, and so forth. You can add a group of thirds to another group of thirds and then find out how many thirds you have in total, but if you try to add thirds to quarters, what do you get? Not thirds, and not quarters, but some mix of the two. What is the sum of 2 apples and 3 Oranges? Five fruit. This doesn't work for numbers, however. The sum of 1/3 and 1/4 is two fractions, but that doesn't tell you anything, you want a specific number. You can get that by converting them both to twelfths. Then you have 4/12 and 3/12 which adds up to 7/12, an actual number.

Q: Why do denominators need to be the same when adding fractions?

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Not always but they need to have the same denominators when adding or subtracting them.

If the denominators are not the same, then you have to use equivalent fractions which do have a common denominator . To do this, you need to find the least common multiple (LCM) of the two denominators.

Yes. When multiplying and dividing fractions your denominators do not have to be the same. The denominators only haveto be the same if you are subtracting or adding them.

you must make the denominators the same first in order to add them once they are added, the denominators stay the same and the top combines

The denominators must be the same, the numerators can be different.

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Not always but they need to have the same denominators when adding or subtracting them.

If the denominators are not the same, then you have to use equivalent fractions which do have a common denominator . To do this, you need to find the least common multiple (LCM) of the two denominators. To add fractions with unlike denominators, rename the fractions with a common denominator. Then add and simplify.

Ensure that the denominators are the same when adding or subtracting fractions.

When adding or subtracting fractions their denominators must be the same

If the denominators are not the same, then you have to use equivalent fractions which do have a common denominator . To do this, you need to find the least common multiple (LCM) of the two denominators.

It depends what you are doing with the fractions. If you are multiplying or dividing fraction, the denominators do not need to be the same and the calculation can be carried out immediately. If you are adding or subtracting fractions, the denominators must be the same; if you have different denominators, the fractions must first be changed into equivalent fractions with the same denominator. When the denominators are the same (or have been made the same as equivalent fractions from being different) the calculation can be carried out.

Subtracting fractions is similar to adding fractions. If the fractions have the same denominator, you subtract the numerators. If the fractions have different denominators, you have to convert to a common denominator first.Subtracting fractions is similar to adding fractions. If the fractions have the same denominator, you subtract the numerators. If the fractions have different denominators, you have to convert to a common denominator first.Subtracting fractions is similar to adding fractions. If the fractions have the same denominator, you subtract the numerators. If the fractions have different denominators, you have to convert to a common denominator first.Subtracting fractions is similar to adding fractions. If the fractions have the same denominator, you subtract the numerators. If the fractions have different denominators, you have to convert to a common denominator first.

Yes. When multiplying and dividing fractions your denominators do not have to be the same. The denominators only haveto be the same if you are subtracting or adding them.

If the denominators are not the same, then you have to use equivalent fractions which do have a common denominator . To do this, you need to find the least common multiple (LCM) of the two denominators. To add fractions with unlike denominators, rename the fractions with a common denominator.

If the denominators are not the same, then you have to use equivalent fractions which do have a common denominator . To do this, you need to find the least common multiple (LCM) of the two denominators. To add fractions with unlike denominators, rename the fractions with a common denominator. Then add and simplify.

When adding fractions, you want to make sure that the denominators are the same. It's the same process as the LCM.

You need to change the denominators so they are the same ( by timesing them together) E.g. 1/7 1/2 7x2=14