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Adding and subtracting fractions with unlike denominators
We've already had some good practice adding fractions with like denominators. We'll now add fractions with unlike denominators. This is a very big deal. After this tutorial, you'll be able to add, pretty much, any two (or three or four or... ) fractions!
A great way to learn how to add fractions with unlike denominators is to do so with denominators in units of 10 and 100. Like this...
Practice adding fractions that have denominators of 10 and 100.
How to add and subtract fractions.
To solve this problem, we need to find the least common multiple to get at the common denominator. Can you help? We bet you can!
To add these fractions we need to find a common denominator. The answer can be expressed as a mixed number. Let's try together.
Practice adding fractions that have different denominators.
If you conquered adding fractions with different denominators, then subtracting fractions will be a snap. Don't worry...we'll take it slow and explain every step.
Practice subtracting fractions that have different denominators.
Use a number line to add fractions with different signs.
Practice adding and subtracting positive and negative fractions.