Grade 4 - Progress in Mathematics

Subtract Larger Numbers

3-8

U.S. Rivers (Length in Miles)

Colorado (Texas) 862 Mississippi 2348

Porcupine 569 Missouri 2540

Rio Grande 1900 Tennessee 886

Study these examples.

The Mississippi is the second

longest river in the United

States. How much longer

is it than the Colorado River?

To find how much longer,

subtract: 2348 
862.

Subtract More tens are needed. More hundreds are needed.

the ones. Regroup. Subtract. Regroup. Subtract.

12

2 14 1 2 14

2 3 4 8 2 3 4 8 2 3 4 8


 8 6 2 
 8 6 2 
 8 6 2

6 8 6 4 8 6

3 hundreds 4 tens  2 thousands 2 hundreds 

2 hundreds 14 tens 1 thousand 12 hundreds

Subtract the

Use addition or estimation to check.

thousands.

12

1 2 14

2 3 4 8


 8 6 2

1 4 8 6

1486  862  2348

or

2300 
 900  1400

The Mississippi is 1486 miles longer than the Colorado River.

13 12 9

5 3 10 0 2 15 5 12 8 13 3 10 15

7 6 4 0 $ 1. 3 5 $ 6 2. 9 3 2 4 , 0 5 7


 4 1 9 5 
 .8 9 
 3 9.0 5 
 1 3 , 9 6 1

3 4 4 5 $. 4 6 $ 2 3. 8 8 1 0 , 0 9 6

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