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Current time:0:00Total duration:2:30
CCSS.Math: ,

Video transcript

now let's do the exact same addition problem that we did in the last video but I'm going to expand out these numbers so that we really understand what's going on when we're doing all of this carrying so this 5 is in the hundreds place so it really represents five hundreds or five hundred three represents three tens because in the tens place so it represents 30 and the six well just represents six ones or six likewise this three represents three hundred this nine is nine tens or ninety and this 8 just represents eight ones or eight and now we can add these two up now let's start let's start in the rightmost column this one's column six plus eight we've already figured out is equal to 14 which is the same thing as 10 plus 4 10 plus 4 10 plus 4 so let's write the part that's not a multiple of 10 in this ones column so let's put the 4 there and the part that is a multiple of 10 we can now carry into this tens column and that's just to keep track of it just to make sure that we don't lose that 10 we're putting it into the tens column now we can add all the tens 10 plus 30 plus 90 we've already figured out is a hundred and thirty well the part that is not a multiple of a hundred we can write in this tens column so the 30 part and the part that is a multiple of 100 we could put in the hundreds column so we could put the hundred right over here notice we've just carried a 1 but they're essentially we've carried a hundred because we put a 1 in the hundreds place 10 plus 30 plus 90 is a hundred plus 30 this is equal to 100 100 plus 30 that's all we've done now we can add the hundreds 100 plus 500 plus 300 we've already figured out is 900 so we could write it as 900 and we're done we figured out that 500 plus 30 plus 6 plus 300 plus 90 plus 8 is equal to 900 plus 30 plus 4 which is the same thing as 934 so hopefully this gives you a little bit more sense of what we're doing when we carry the 1 every time 6 plus 8 is 14 we carried the one that one represents ten it represents this ten right over here just so we don't lose track of it then we say 10 plus 30 plus 90 is equal to 130 so that's 30 plus 130 plus 100 then we add the hunters together we get 900 900