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Addition and subtraction of fractions

Video transcript

We're asked to select which fractions add together to make 25 over 22, or 25/22. You can use as many fractions as you need. Put all unused fractions into the trash can. So let's think about how we could do this. So I actually want to use the largest fraction first, just so I can get pretty close. So I'm going to make 16/22. And let's see, if I add 8/22 to that, then that's going to get me to--let's see, 16 plus 8, that gets me to 24/22. This is 16/22 plus 8/22 is going to get me 24/22. And if I get one more, that gets me to 25/22. And then I could put these unused ones down here in the trash can. So I'm going to put these unused ones down here. And let's actually check our answer. Got it right. And there's multiple ways that we could have actually done this. Actually, it's not clear that there's multiple ways that we could have done this. Let's see-- is there any other way? Yeah, because even if we did the 2 and the 4 here, we would have to get to-- let's see, 8 would get us to-- this is 2/22 plus 4/22 is 6/22, plus 8/22 is going to be 14/22, yeah. And then if you put 16/22, there's going to be too many. So actually, the way we did it was the way that you've got to do it. So the 2 and the 4 I'm going to put in the trash can. And 16 of something plus 1 of something plus 8 of something is going to be 25 of that something. And in this case, the something that we're talking about are 22nds.