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## 4th grade

### Course: 4th grade > Unit 8

Lesson 5: Adding and subtracting mixed numbers- Adding mixed numbers with like denominators
- Subtracting mixed numbers with like denominators
- Add and subtract mixed numbers (no regrouping)
- Mixed number addition with regrouping
- Subtracting mixed numbers with regrouping
- Add and subtract mixed numbers (with regrouping)

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# Subtracting mixed numbers with like denominators

Sal practices subtracting mixed numbers with common (like) denominators.

## Want to join the conversation?

- If you are alive like this post(16 votes)
- this helps me a lot(12 votes)
- if your alive like this post(9 votes)
- this is so easy am i right?(8 votes)
- It is so hard to subtract fractions.😭

Can you explain to me how?

I can not understand.

Thanks!(5 votes)- Its bascially like 5-1=4 but a fraction example is 3/4-1/4=2/4. Hope this helps :)(5 votes)

- I understand the work, but I just don't know how to type it on the computer.(6 votes)
- If you are a person upvote this question.

Also at0:10can't you do mental math instead of doing all the other ways?(6 votes) - if you are a robot upvote this comment(4 votes)
- i am a ghost cuz i did #gocommitdie(2 votes)

- this rally help me out a lout danes(4 votes)

## Video transcript

- [Instructor] Let's say
that we want to figure out what is seven and 11/12
minus one and 6/12. Pause this video and see
if you can figure that out. All right now let's work on this together. So there's a couple of ways
that you could approach this. You can view this as the same
thing as seven plus 11/12 and then minus one and you
might be tempted to say minus one and then plus 6/12 but
remember you're subtracting not just the one you're
subtracting one and you're subtracting 6/12 so minus one minus 6/12. Now why is that useful to
think about it that way? Well now you can think about
the whole numbers so you can say this is going to be
seven minus one plus 11/12, plus 11/12 minus 6/12, minus 6/12. And so seven minus one is six,
so it's going to be six plus now if I have 11 of
something in this case 12ths and I'm subtracting six of
them away six of the 12ths, I'm gonna be left with five of
those somethings, five 12ths. So it's going to be six plus
5/12 which is the same thing as six and 5/12. Now as you get more used
to this you could do some of this maybe even in your
head, you could say hey look, look at the whole number
parts, seven minus one is going to give me six and then
if I say 11/12 minus 6/12 is going to give me 5/12 so
that takes up a little bit less space. Another way that you might
see this approached is you can rewrite this as seven and 11/12
minus, minus one and 6/12. Let me do the 6/12 in that
blue color that I'm using for the fraction parts,
6/12 and then I would first focus on the fractional parts
and I'd say 11/12 minus 6/12 is 5/12 and seven minus one
is six and I got six and 5/12. So many different ways to
approach the same thing and at the end of the day
they really are the same underlying idea.