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Adding and subtracting fractions with unlike denominators

6 videos
4 skills
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!

Adding fractions with unlike denominators: units of 10

VIDEO 4:25 minutes
A great way to learn how to add fractions with unlike demoninators is to do so with denominators in units of 10 and 100. Like this...

Adding and subtracting fractions

VIDEO 9:50 minutes
How to add and subtract fractions.

Adding fractions: different denominators

VIDEO 4:06 minutes
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!

Adding fractions: common denominator

VIDEO 2:33 minutes
To add these fractions we need to find a common denominator. The answer can be expressed as a mixed number. Let's try together.

Subtracting fractions: different denominators

VIDEO 4:24 minutes
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.

Adding fractions with different signs

VIDEO 6:22 minutes
As we learn about fractions, this is a good time to add the complexity of negative numbers as fractions. Let's practice adding fractions with different signs!