Adding mixed numbers with like denominators
About this video
The video adds 2 and 5/13 plus 7 and 6/13 by splitting each mixed number into its whole number part and fraction part. It adds the whole numbers (2 + 7 = 9) and the fractions with the same denominator (5/13 + 6/13 = 11/13) to get 9 and 11/13.
You'll be able to
- split a mixed number into a whole number part and a fraction part.
- add fractions that have the same denominator.
- add two mixed numbers with like denominators.
Key words
- mixed number
- A number made of a whole number and a fraction, like 2 and 5/13.
- denominator
- The bottom number of a fraction; it tells how many equal parts make a whole.
- numerator
- The top number of a fraction; it tells how many parts you have.
- whole number
- A counting number with no fraction part, like 2, 7 or 9.
Transcript
Let's add these two mixed numbers. 2 and 5/13 plus 7 and 6/13. And the way I like to think about in my head, I like to separate out the mixed numbers into the whole number component and the fractional component. So we can rewrite 2 and 5/13 as 2 plus 5 over 13.
And then we can write that plus. And then 7 and 6/13, we can rewrite as plus 7 plus 6/13. So all I did is I rewrote this. And I essentially expanded it out. I broke up the mixed numbers into their whole number parts and their fractional parts. And then what I like to do is I like to add the whole number parts.
So this 2 plus this 7, so I'll do that. So I'll do the 2 plus 7 over here. I'll add those up. And to that, I will add the fractional parts. So to that, I will add the 5/13 to the 6/13. So if we add the whole number parts, 2 plus 7 is 9, and the fractional parts, they already have the same denominator in this problem.
5/13 plus 6/13, same denominator. You're going to get 11/13. 5 plus 6 is 11. So you get 9 plus 11/13. Well, that's just the same thing as 9 and 11/13. And we are done.
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