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Current time:0:00Total duration:7:42

Video transcript

welcome to the presentation on basic addition I know what you're thinking Sal addition doesn't seem so basic to me well I apologize I hope hopefully by the end of this presentation or in a couple of weeks it will seem basic so let's get started with I guess we could say some problems well let's say I start with a with a with an old classic 1+1 and I think you already know how to do this but I'll kind of show you a way of doing this in case you don't have this memorized or you you haven't already mastered this you say well if I have one let's call that a avocado if I have one avocado and then you were to give me another avocado how many avocados do I now have well it's let's see I have one two avocados so one plus one is equal to two now I know what you're thinking that was too easy so let me give you something a little bit more difficult I like the avocado so I might I might stick with that theme what is 3 plus 4 um this is I think a more difficult problem well let's go let's stick with the avocados and in case you don't know what an avocado is it's a it's actually a very delicious fruit it's actually the the fattiest of all the fruits you probably didn't even think it was a fruit even if you ate one so let's say I have 3 avocados 1 2 3 right 1 2 3 and let's say you were to give me 4 more avocados so let me put this 4 in in yellow so you know that these are the the ones you're giving me 1 2 3 4 so how many total avocados do I have now that's 1 2 3 4 5 6 7 avocados so 3 plus 4 is equal to 7 and I'm going to troduce you to another way of thinking about this it's called the number line actually I think this is how I do it in my head when I forget if I don't have it memorized so a number line I just write all the numbers in order and I go high enough just so I can all the number I'm using or kind of in it so you know the first number is zero which is nothing maybe you don't know and now you know and then you go to one two three three four five six seven eight nine ten keeps going eleven so we're saying three plus four so let's start at three so I have three here and we're gonna add 4 to that three so all we do is we go up the number line and we go to the right on the number line four more so we go one two three four notice all we did was just increased it by 1 by 2 by 3 by 4 and then we ended up at 7 and that was our answer we could do a couple of different ones we could say what is what if I asked you what 8 plus 1 is mmm 8 plus 1 well you might already know it you know plus 1 is just the next number but if we look at the number line you started eight and you add one eight plus one is equal to nine let's do some harder problems and just so you know if you're a little daunted by this initially you can always draw the circles you can always do the number line and eventually over time the more practice you do you know you'll hopefully memorize these then you'll do these problems in like half a second I promise you you just got to keep practicing let's say I want to draw the number line again actually I have a line tool so I shouldn't give you all those ugly looking lines that I've been giving you look at that look at that that's amazing okay so that's a nice looking line I'm gonna feel bad to erase it later on so let me draw a number line 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 so let's do a hard problem what is I would do it in different colors now 5 plus 6 so if you want you could pause the video and try this you might already know the answer and the reason why I say this is a hard problem is because the answer has more numbers than figures so you can't necessarily do it on your fingers so let's get started with this problem actually my phone is ringing but I'm going to ignore the phone because you're more important ok let's start at the 5 so we started at the 5 and we're gonna add 6 to it so we go 1 2 3 4 5 6 we're at 11 so 5 plus 6 is equal to 11 now I'm gonna ask you a question what is 6 plus 5 well we're now gonna see that can you switch the two numbers and get the same answer well let's let's try that I'm gonna try a different color so we don't get all confused so let's start at 6 right ignore the yellow for now and add 5 to it 1 2 3 4 5 huh we get to the same place and I think you you might want to try this on a bunch of problems and you'll see it always works out that it doesn't matter what order you know if 5 plus 6 is the same thing as 6 plus 5 and that makes sense if I have 5 avocados and you give me 6 I'm gonna have 11 if I have 6 avocados and you gave me 5 I'm gonna have 11 either way let's do a couple since this number line is so nice I'm gonna do a few more problems using it although I thought use it I'm sure I'll just continue to confuse you because I'll write so much on top of it but let's see I'll use white down what is what is eight plus seven well if you can still read this eight is right here right we're gonna add seven to it one two three four five six seven we go to 15 eight plus seven is fifteen so hopefully that gives you a sense of of how to do these types of problems and more than I guess this and you're gonna learn multiplication a little bit but but these types of problems are when you're getting started off in mathematics these kind of require the most practice and to some degree you have to start memorizing them but over time you know when you hope when you look back good I want you to remember how you feel while you're watching this video right now and then I want you to watch this video in like three years and remember how you felt when you're watching it now and you're gonna be oh my god this this was so easy cuz you're gonna learn so fast so anyway I think you have an idea if you don't know the answer to any of the addition problems that we give you the exercises you can you can press the hints and it'll draw circles and you could just count up the circles or if you want to do it on your own so you get the problem right you could draw the circles or you could draw a number line like we did in this presentation I think you might be ready to tackle the the addition problems have fun