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Adding 2-digit numbers without regrouping 1 | Addition and subtraction | 1st grade | Khan Academy


less than 1m read
·Nov 11, 2024

  • Try to pause the video and figure out what 71 plus 24 is. All right, now let's do this together. So let's think about what 71 actually means. Well, we have a one in the ones place. Let me make this clear. So this is the ones place and we have one one. So that's that one one right over there.

And then the tens place - in the tens place we have seven, so we have seven groups of ten. One, two, three, four, five, six, seven groups of ten. So this really means seven tens and one one. This right over here, 71 boxes.

Now we're going to add to that two tens. We're gonna add to that two tens; you see them here. One ten, two tens and four ones. And four ones. So what is that going to be?

Well, let's first think about the ones. We have one one and four more ones. Well, that's going to be five ones. That's going to be five ones, so we can count them right over there. This is five ones right over there. One one plus four ones is five ones.

And then when you look at the tens; seven tens plus two tens. Well, if you combine all of these together - if you combine all of these together you are going to have nine of these groups of ten. We're gonna have nine tens.

Seven tens plus two tens is nine tens. So we're left with nine tens which we see right over here and five ones. And five ones. Well, what's another way of saying nine tens and five ones? Well, that's 95, and we're done.

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