Grade 4 - Progress in Mathematics

Four-Digit Addition

3-3

th h t o

1

1 2 7 9


2 3 5 5

4

th h t o

1 1

1 2 7 9


2 3 5 5

3 4

th h t o

1 1

1 2 7 9


2 3 5 5

6 3 4

th h t o

1 1

1 2 7 9


2 3 5 5

3 6 3 4

Find the sum of 1279 
2355.

First, estimate: 1279 
 2355

1000 
 2000  3000

Then add: 1279 
2355.

Add the ones. Add the tens. Add the Add the

Regroup. Regroup. hundreds. thousands.

14 ones  13 tens 

1 ten 4 ones 1 hundred 3 tens

The sum is 3634.

Study these examples.

1 1 1 1 1 1

4 7 8 0 $ 6 4. 3 8 $ 5 0. 6 7


 2 9 5 6 
 1 7.2 5 
 5.4 5

7 7 3 6 $ 8 1. 6 3 $ 5 6. 1 2

Think

3634 is close to 3000.

The answer is reasonable.

Choose a method to estimate. Then add.

1. 3165 2. 4227 3. 2774 4. 5538
   
   2917
   1905
   6407
   614


2. 4168 6. 6075 7. 8264 8. 9438
   
   3454
   2845
   1349
   395

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