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Intro to adding mixed numbers

Sal adds 2 mixed numbers with common (like) denominators. 

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  • aqualine ultimate style avatar for user kahnclifford
    Will it make sense if you convert those mixed numbers to improper fractions then convert it back again to mixed numbers to get also the same correct answer?

    Example:
    (Convert to improper fraction)
    2 4/7 = 18/7
    3 2/7 = 23/7

    (Add both improper fractions)
    18/7 + 23/7 = 41/7

    (Convert back to mixed number)
    7÷41 = 5r6
    = 5 6/7

    Same with:
    2 4/7 + 3 2/7 = 5 6/7
    (17 votes)
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  • duskpin seed style avatar for user Coolgirlsk8ts
    what is the easiest way to add fractions
    (5 votes)
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  • blobby green style avatar for user Mark Mellona
    what happens if the answer is improper
    (5 votes)
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  • male robot hal style avatar for user tanav
    How do you do 5 6/8+8 5/6?
    (5 votes)
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    • spunky sam red style avatar for user k. arun
      First, you would add the fractions:
      6/8 + 5/6
      To do this, you have to find their common denominator:
      What is the least common multiple of the denominators, 6 and 8? 24.
      Then, you make the fractions equivalent with the same denominator.
      if 5/6 had to become x/24, what would x equal? Well, what is 6 being multiplied by to make 24? 4. Whenever you multiply the denominator by something (in this case, 4) you also have to multiply the numerator. In this case, 5/6 would equal 20/24, which is equivalent.
      You do the same thing for 6/8:
      It becomes (6*3)/24, which equals 18/24.
      P.S. To check this, you can always simplify your new fraction to make sure it is still equivalent.
      Then, you add these fractions together. So:
      20/24 + 18/24 = 38/24
      This is an improper fraction. So now, you have to convert it to a mixed number. 24 goes into 38 one time with 14 left over. So we get:
      1 14/24, or simplified, 1 7/12.
      Now we add the whole numbers:
      5 + 5 = 10.
      Then, we add the mixed number to 10 which makes 11 7/12.
      Your final answer is 11 7/12.
      Hope that helped.
      (7 votes)
  • starky seedling style avatar for user zack
    i cant hear it please help me somebody
    (5 votes)
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  • male robot johnny style avatar for user scasas2027
    Now I understand how to add mixed numbers.👍
    (7 votes)
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  • leafers seedling style avatar for user kr10103
    no i don,t understand can someone help me here🥺🥺🥺🥺🥺🥺
    (6 votes)
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  • aqualine ultimate style avatar for user Nema
    When it comes to step 3 I get confused when you have to put your fraction in "Simplest Form".Is is ok if anybody who know it can explain it in a different way?:3Pwease?
    (3 votes)
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  • blobby green style avatar for user Chris Vonweller
    i need to learn subtracting mixed number's
    (6 votes)
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  • purple pi pink style avatar for user stustu21
    Why don't you add the denominator?
    (4 votes)
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Video transcript

- [Voiceover] Let's give ourselves some practice adding mixed numbers. So let's say I want to add two, let me write it this way. Let's say I want to add two and four sevenths plus three and two sevenths, three and two sevenths. I encourage you to pause this video and try to think about what this is going to be. Well there's a couple of ways that you could tackle it. One way, you could say, well let me just add the nonfraction parts. You could say that two plus three is equal to five, and then you could say that four sevenths plus two sevenths is equal to well four sevenths plus two sevenths is gonna be equal to six sevenths. Hey, wait, wait, wait, how did I, how did I do that? How did I just only add the fraction parts or add the whole parts? Well the way I did that is because two and four sevenths is the same thing as two plus four sevenths. Two and four sevenths, same thing as two plus four sevenths. And then plus three and two sevenths is the same thing as three plus two sevenths, so all I did over here, two and four sevenths plus three and two sevenths, is two plus four sevenths plus three plus two sevenths. And you can swap the order in how this happens. So you could take, you could just switch the order and say this is going to be two plus three, two plus three, plus four sevenths, plus two sevenths. And what we just figured out was that two plus three is equal to five, right over here, and that four sevenths plus two sevenths is equal to six sevenths, just like that. Now let's do a more interesting example. Let's do, let's say that I have three and three fifths, three and three fifths plus five and four fifths. Now what is this going to be equal to? Well if you do the same technique, if you add the three plus the five, you're going to get eight, and then if you add the three fifths plus four fifths, you would get seven fifths. So you get eight and seven fifths. And this wouldn't be wrong. This is eight and seven fifths, if you add these two things together, but it's a little bit strange here because seven fifths is bigger than a whole. So to get a better sense of what number's really being represented here, I want to rewrite this. So eight and seven fifths, this is the same thing as eight plus, and instead of seven fifths, we could say this is the same thing as five fifths, which is a whole, plus two fifths. Now why is that interesting? Because five fifths, notice five fifths plus two fifths, that's seven fifths right over there. Or you can consider five fifths to be one, so this is eight plus one, which is nine, and two fifths, nine and two fifths. So all I did here, I added it the same way that I did the first problem a few seconds ago. But when I realize this fraction part is greater than one, I separated it into one and then a fraction that is less than one, and that whole, I was able to add to the eight to get to nine, and then I would have two fifths left over. Eight and seven fifths, because five fifths is a whole, is the same thing as nine and two fifths. So if I wanted to write this in, I guess, a clearer way, I would say this is nine and two fifths. Three and three fifths plus five and four fifths is nine and two fifths, and once again, we say wait, three plus five is only eight, how did I get a nine? Well that's because three fifths plus four fifths is greater than one.