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## Staging content lifeboat

### Course: Staging content lifeboat>Unit 14

Lesson 14: Adding and subtracting fractions with like denominators

# Subtracting fractions with like denominators

Sal subtracts 8/18-5/18. Created by Sal Khan and Monterey Institute for Technology and Education.

## Want to join the conversation?

• I dont like COVID-19 ;(
• who doesn't honestly
• 4/5 divided by 2/5 equals 30/12 how is that wrong?
• 4/5 divided by 2/5 equals 4/5*5/2(because of reciprocal) which is 4/2 or 2. That's why it's wrong. Hope this helps!
• I have a hard time remembering and understanding what he says because he’s going way too fast…. Can there be a slower version please?
• Hi. Its Yagnesh here. if you don't understand what sal says, You need to do the following in order to slow down the video. you click on the setting button (looks like a wheel). then click on 'playback speed.'it will be normal. if you click on 0.75 or 0.5, it will become slower. Hope that helps.
• When subtracting fractions with the same denominators do we have to change the denominators?
• no the denominater stays the same
• 4/5 divided by 2/5 equals 30/12 how is that wrong
• why doesn't the denominators changes
• Becuase its subtracting with like denominators so they will not change they will stay the same because like means the same
• How is it possible to have a negative fraction? If you think about fractions as pieces of pie, wouldn't it be impossible to have negative pieces of pie?
• I understand your reasoning about that, but it doesn't quite work, with that logic you cant have negative whole number either, because you cant have a negative whole pie.
think of it like this; a fraction is a part of a number, right? well, you can have a negative part of a number as well as a negative number. look at this number line-
-1___________________0____________________1
something has to go in between those spaces!
hope this helps!
• What is it if the fraction 16/12 divided by 3/12 ? Will it work?