Adding within 20 using place value blocks

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About this video

This video shows how to find 8 + 6 with blocks by making a group of 10. All 8 blocks plus 2 of the 6 make a ten, leaving 4 ones, so 8 + 6 is one 10 and four ones, or 14.

You'll be able to

  • add two numbers within 20 by making a group of 10 first.
  • say how many tens and ones are in a sum like 14.

Key words

group of 10
Ten blocks put together into one bar.
ones
Single blocks that are not part of a group of 10.
place value
What a digit is worth because of where it sits, like the tens place or the ones place.
Transcript

- [Instructor] What we wanna do in this video is think about what is equal to eight plus six, and to help us out, we have eight blocks shown right over here, and we have another six blocks shown in this pink color. So pause this video and see if you could figure it out.

So there's a lot of ways to approach it, but one way that I like to do it is, let me see if I can make a group of 10 out of some of these blocks and then see how many of them are left over. So if I want to make a group of 10, I would use all of these eight. So one, two, three, four, five, six, seven, eight, and then I would need two more and I could get those two more from this six here, and then I would have one, two, three, four left over.

And to see what that looks like, you can see that we could take all of the eight and then two of the six to make a group of 10, and so I set that up as a whole bar. So we know that our answer is going to have one 10. So this tells us that that is, let me write it this way, one 10 and then how many ones?

Well, we could see that right over here. We have four ones left over. So that is four ones. So if we think about place value, that's one 10 and four ones or 14. We have 10 and another four, which is the same thing as 14.

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