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When you add three of something to four of something, you get seven of something. It doesn't matter what the somethings are. Think of ninths as somethings. If you add three ninths and four ninths, you have to wind up with seven ninths. You can't wind up with seven eighteenths, because you weren't adding eighteenths to begin with.

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โˆ™ 2013-05-16 03:54:49
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Q: Why when you add or subtract a fraction the denominator stays the same?
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How to subtract a fraction from a whole number?

Change the whole number into an improper fraction with the same denominator as the fraction and then subtract accordingly

How is subtracting fraction when numerator and denominator is the same?

If the numerator and denominator are the same, the fraction simplifies to 1. And you should be able to subtract 1!

How do you subtract mixed fractions when they have the same denominator?

The numerator of the answer is the result of subtracting the numerators of the fractions, and the denominator of the fraction is the same as the common denominator.

Why is it easy to subtract and add with the fraction that has the same donominator?

Because if you have the same denominator then you don't have to find the common denominator.

When adding or subtracting fractions do you change the numerator?

you subtract the numerator but the denominator stays the same.

When you add or subtract fractions with the same denominators what happens to the denominator in your answer?

It stays the same. Only the numerators change.

How do you subtract fractions without mixed numbers?

First, turn the fraction into a improper fraction. Then find a common denominator between the two numbers. After this, subtract strait across, but leave the denominator the same.

How do you subtract fractions with the same denominator?

subtract the top two and the bottom stays the same.....for example; 4/8-3/8=1/8

Can you subtract a fraction with the same denomintor and get a different denominator?

Only after simplification. If you subtract numbers with the same denominator, you have to put the original denominator in the result, but you can later simplify this, in some cases. A simple example: 3/4 - 1/4 = 2/4. Same denominator, but this can be simplified to 1/2.

How do you write a mixed number to a fraction?

You multiply the denominator by the whole number, then add the numerator of the original fraction to get the numerator of your new fraction. The denominator stays the same as the original. Then you simplify into lowest terms.

When you subtract fractions do you subtract the denominator?

No. If the denominators are the same, you subtract the numerators. If the denominators are different you have to find the least common denominator.

What happens to the size of the fraction when the numerator stays the same but the denominator increases?

The fraction decreases. 1/3 is smaller than 1/2.

What the denominator should be when subtracting a fraction from a whole number?

The denominator should be the same as the denominator of the fraction.

When you divide a fraction by a fraction do you have to have the same denominator?


How do you add and subtract fractions with the same denominator?

it stay the same when you subtract fractions and when you add fractions.

How do you subtract a fraction from a fraction?

well its simple here is an example 3/8-2/8=1/8 you leave the denominator the same and 3-2=1

How can you make an in proper fraction into m a mixed number?

Divide the denominator into the numerator. The number of times it goes, is the whole number. The remainder is the new numerator and the denominator stays the same unless you need to reduce the fraction.

How do you find a fraction with the same denominator?

Simply change the numerator and you will have another - different - fraction wit the same denominator.

How do you subtract fractions with unlike?

Before you can add or subtract, both fractions must have the same denominator, andmaking that change without changing the value of either fraction is your job. The bestchoice for a 'common' denominator is usually the least common multiple of the originaldenominators.

What is similar fraction?

Have the same denominator

Do you have to have the same denominator to divide a fraction?

No, you do not.

How do you subtract mixed numbers that do not have the same denominator?

Find a common denominator of the fraction parts (the least common denominator is the popular choice). If the fraction part of the subtrahend is bigger than that of the minuend, you need to subtract 1 from the integer (whole number) part of the minuend and add it (as a fraction) to the fraction part. For example, 5 3/7 becomes 4 10/7. Then you can subtract the fraction parts by subtracting the numerators, and subtract the integer parts, provided the integer part of the minuend is greater than or equal to that in the subtrahend. If not, reverse the roles of the minuend and subtrahend and use the above method to subtract, then make the sign of the difference negative.

What part of the fraction does not change when you add or subtract?

If you find the common denominator for the fractions, then the bottom will stay the same :) BUT sometimes it is diffacult to find the common denominator so you may need help

What is the meaning of addition and subtraction of similar fraction?

Similar fractions are fractions with the same denominator. In order to add or subtract fractions they need to be similar.

How do you subtract a fraction from another fractions?

First you get a common denominator, for example, 1/4 - 1/2 would be changed to 1/4 - 2/4 because what ever you do to change to denominator, you have to do the same with the numerator. Then you subtract the numerators and keep the denominator the same. Example: 1/4 - 2/4= -1/4.