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Current time:0:00Total duration:4:06

Video transcript

what I want to do in this video is think about the different ways to make five so what do I mean about that so right over here we have three plus something so there's some unknown number right over here three plus something is going to be equal to five and in this diagram we have three circles here that represents the three and then we have five boxes one two three four five and so how many more circles do we need in order to fill up all the five boxes we've clearly already filled three well let's think about it we just have to add one and two circles now we have a total of five three blue ones and two of this purple color or that I guess this pink color so we see that three plus two three plus two is equal to five so that mystery number here that blank is two three plus two is equal to five now over here we have two plus some mystery number is equal to five again and once again we have five spaces and two of them are filled in with these kind of purple pink stars so how many more do we have to fill it in order to fill in all five boxes two plus what is equal to five and I encourage you to pause the video and think about it so I'm assuming you've had a go at it so let's think about how many more of these boxes we need to fill in in order to fill in all five of them so we need to fill in one two and three of the boxes in order to fill out all five now we have five stars we have two of the pink ones and we have three of the blue ones so we can say that two plus three the mystery number here is three two plus three is equal to five let's do a few more of these so here I have four plus some mystery number is equal to five and I filled out four of the five boxes how many more do I need to fill in in order to have five things in order have all five boxes filled out well we see very clearly here that there is exactly one box that we need to fill in or one box that we need to add to the other four so we see that 4 plus 1 4 plus 1 is equal is equal to 5 now let's go the other way we have the five boxes only one of them is filled in how many more of these smiley faces do we need to add in order to fill in all the boxes or another way of thinking about it we have one how many more do we need to add to one to get to five and like always encourage you to pause the video and think about it on your own well let's see we can add one we can add two we can add three and four yellow smiley faces so we could say one one we have one white smiley face plus one two three four yellow smiley faces is equal to five and you see a pattern here let's look at let's start at the beginning three plus two is equal to five and two plus three is equal to five when you hit three filled in you did it two more to get to five when you had two filled in you did it three more to get to five notice three plus two two plus three same thing over here four plus one is equal to five 1 plus 4 is equal to five