### Lesson List

 TH H T O 1 5 2 8 + 4 8 3 3 5

When adding four-digit numbers, you may need to regroup the hundreds as thousands.   Always work from right to left.

Look at the example below.

 TH H T O 1 5 2 8 4 8 3 3 11

Regroup the ten!

 TH H T O 1 1 5 2 8 4 8 3 3 1

 TH H T O 1 1 5 2 8 4 8 3 3 6 1

 TH H T O 1 1 5 2 8 4 8 3 3 13 6 1

Regroup the 10 hundreds!

 TH H T O 1 1 1 5 2 8 4 8 3 3 3 6 1

thousands!

 TH H T O 1 1 1 5 2 8 4 8 3 3 6 3 6 1

Complete the problems below.

 TH H T O 2 4 5 7 5 7 6 8

Carry the ten!

 TH H T O 2 4 5 7 5 7 6 8 5

 TH H T O 1 2 4 5 7 5 7 6 8 5

Regroup the tens!

 TH H T O 1 2 4 5 7 5 7 6 8 2 5

Carry the 10 hundreds!

 TH H T O 1 1 2 4 5 7 5 7 6 8 2 2 5

 TH H T O 1 1 1 2 4 5 7 5 7 6 8 2 2 5

 TH H T O 1 9 8 5 3 2 4 6

 TH H T O 1 6 4 5 2 7 8 5

 TH H T O 3 9 7 5 4 3 4 7

 TH H T O 2 8 8 8 4 7 6 5

 TH H T O 3 5 5 5 3 6 7 8

 TH H T O 2 7 9 8 3 6 6 6

 4 4 4 3 4 6 7 8

 3 3 3 9 5 8 9 4

 2 7 3 1 3 4 6 9

 2 4 5 6 3 5 7 9

 1 3 5 7 2 4 6 8

 2 5 7 5 4 5 2 5

 3 4 3 4 3 5 3 5

 2 1 2 1 1 9 1 9

 2 7 2 9 3 4 3 5

 2 9 9 9 3 9 8 7

 1 2 3 4 7 8 9 1

 3 7 7 7 4 4 5 6