1. How do you use tens and near tens to add?

4. A common misunderstanding is that in addition the order of the addends changes the sum. That is not true The order of the addends does not change the sum = 17 and = 17. This is called the commutative property of addition.

6. To build power numbers like 10 you need to know what it is composed of
To build power numbers like 10 you need to know what it is composed of. 10 can be decomposed into 2 and = 10 and 8 +2 = 10.

7. To build power numbers like 10 you need to know what it is composed of
To build power numbers like 10 you need to know what it is composed of. 10 can be decomposed into 3 and = 10 and 7 +3 = 10.

8. To build power numbers like 10 you need to know what it is composed of
To build power numbers like 10 you need to know what it is composed of. 10 can be decomposed into 4 and = 10 and 6 +4 = 10.

9. To build power numbers like 10 you need to know what it is composed of
To build power numbers like 10 you need to know what it is composed of. 10 can be decomposed into 5 and =

10. Tens Ones 10 is 1 ten and 0 ones. 15 is 1 ten and 5 ones

11. Tens
Ones
If we wanted to add 10 plus 9 that would equal 1 ten and 9 ones or 19. We would simply add the ones place and the tens place. With the 0 in the ones place the 9 can be easily added. I can see this in my head.

12. Tens
Ones
If we wanted to add 10 plus 15 that would equal 5 ones and 2 tens or 25. We would simply add the ones place and the tens place. With the 0 in the ones place the 5 can be easily added.

13. We can also use near tens, like 9, to add.
. In the example 9+2 we can see our 9 blocks. Then decompose the 2 into 1 and = 10 that = 11 so 9+2 = 11