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# Adding 8 + 7

CCSS.Math:

## Video transcript

let's try to think about what eight plus seven is equal to and we could imagine that this is like taking eight tomatoes and adding seven blueberries and then saying how many pieces of fruit do you have in total and I encourage you to pause the video and try this out on your own so I'm assuming you've given a try so let's let's let's think about it a little bit and the way I'm going to think about it is I'm going to keep adding Tomatoes until I fill up my first bucket of ten and then I'm going to see how many more I have to add to get to essentially add a total of seven so let's let's have one tomato two Tomatoes three tomatoes four Tomatoes five Tomatoes six Tomatoes seven and eight tomatoes now to those eight tomatoes I'm going to add seven blueberries so that's going to be one two and actually I'm going to pause there because I just finished a group of ten this right over here I already I've only added two of the blueberries I still have some more blueberries to add but just with adding those two blueberries I have completed a group of ten so I already have ten pieces of fruit so I can represent that I know since I have a group of ten here that I have one group of ten so this is going to be a two-digit number where the digit on the left is going to be a one but I'm not done adding blueberries I've only added two blueberries now let me add a third three blueberries for blueberries five blueberries six blueberries and seven blueberries so I have a group of ten and then above and beyond filling out that group of ten which is represented here because this is going to be a two-digit number this is the left digit so this one since it's in the tens place it literally represents one group of ten which is right over there and then how many more do I have well I have another I have another five ones five ones right over here so we have one ten and we have five ones so what is 8 plus 7 it is 15 and another way just to remind ourselves what 15 represents the 1 and 15 represents 1/10 let me write it down it represents it represents 1/10 and the 5 represents five ones five ones and so another way of thinking about it 1/10 is the same thing as 10 and five ones is the same thing as five so 8 plus 7 is 15 that was the whole point of this video but we also want to think about what these numbers represent 15 literally represents 1/10 plus 5 ones or 10 plus 5