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# Subtracting 1s using place value

CCSS.Math:

## Video transcript

so right here we have the number 46 we have a 4 in the tens place so it literally represents 4 tens and we see them here 1 2 3 4 tens that's a 10 that's a 10 that's a 10 and that's a 10 each of these are 10 squares so altogether we have 4 tens or 4d squares in purple and then we have a six in the ones place we have a six in the ones place so we have six ones and we see that right over here 1 2 3 4 5 6 so we can write that 46 do the same colors 46 is equal to 4 tens 4 tens and six ones or I could write plus 6 plus 6 ones now let's do something interesting let's subtract let's subtract 4 ones from the 46 so let's think about what it means to take let's take 46 so we're going to start with 46 just the number that we have in front of us and we are going to subtract 4 we are going to subtract 4 what is this going to be equal to how many tens so it's going to be a certain number of tens and it's going to be plus a certain number of ones plus a certain number of ones so I've left blanks right over here so how many tens are we going to have so 46 that's what we started with we're subtracting 4 ones so we're going to subtract one two three four we're going to take away four ones so how many tens do we have well we still have four tens so let's write that that let's write that down we still have four tens but now how many ones do we have well now we only have two ones we only have two ones and so you see when you had four tens and six ones and you subtracted four ones well six ones minus four ones is two ones and so we get 46 let me do that in the same color we get forty I'm having issues here so this is going to be this is going to be 46 minus four is equal to four tens well that's just a four in the tens place so write a four in the tens place and then two ones put a two in the ones place forty two forty six minus four is 42 and you can see that right there in the ones place we just took four from this six