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Current time:0:00Total duration:3:53

Video transcript

let's think about what seven plus six is and I encourage you to pause this video and think about it on your own so I'm assuming you've given a go at it so let's think about it we could view this as seven objects plus six more objects and then think about how many total objects we had so for example we could view it as seven say tomatoes so one tomato two Tomatoes three tomatoes four Tomatoes five six and seven and then to that we're going to add six more objects and let's say they're blueberries and we care about the total amount of fruit so one two three four five and six six blueberries now how many total pieces of fruit do I have in all now well I started with seven so that's seven and so if I keep counting this is seven so this is going to be eight nine ten eleven twelve and thirteen so I now have a total of thirteen pieces of fruit thirteen pieces of fruit now what are other ways that we could have thought about this well we could have also done it on a number line so let's draw ourselves a number line do it in so let's say we have a number let me do this in a color that I haven't used yet actually so let's say I have a number line so just like that and I could start the number line at seven I could start at seven and I'm going to add six more I'm going to move six more up the number line so this was one two three four five six and of course I could keep going it's going to be eight nine ten eleven twelve thirteen and of course you could keep on going but seven plus six you could visualize this as starting at seven and then making six jumps up the number line one two three four five six either way we get we get to 13 another way to think about it is well look we started with seven we added three to get to ten and so we have to add another three which gets us to thirteen and that really goes to the heart of what the number thirteen represents the number thirteen has a one as its left digit this digit is in the tens place so it literally represents 110 so it's 110 plus three plus three ones and you see that right over here that when I added the pieces of fruit this right over here is one group of ten so that's one group of ten and so we had to add three to get to that one group of ten and then so we kind of filled that bucket and then we had three more so we're left when you add seven plus six you fill one whole group of ten and then you have three ones left over so this is the three ones right over here so another way to think about it is seven plus six is the same thing as 10 plus three which of course is 13 so this is the same thing 110 is ten plus three plus three ones thirteen either way you look at it