Grade 4 - Progress in Mathematics

Subtraction: Regroup Twice

3-7

How many more home runs did

Babe Ruth hit than Frank Robinson?

Subtract: 714 
586.

Estimate by rounding: 700 
 600  100

Then subtract.

More ones are needed. More tens are needed. Subtract

Regroup. Subtract ones. Regroup. Subtract tens. hundreds.

10 10

0 14 6 0 14 6 0 14

7 1 4 7 1 4 7 1 4


 5 8 6 
5 8 6 
 5 8 6

8 2 8 1 2 8

1 ten 4 ones  7 hundreds 0 tens 

0 tens 14 ones 6 hundreds 10 tens

Number of Home Runs Hit

Aaron 755 Killebrew 573

Ruth 714 Jackson 563

Mays 660 Schmidt 548

Robinson 586 Mantle 536

McGwire 583 Foxx 534

1 1

1 2 8

 5 8 6

7 1 4

Check.

Babe Ruth hit 128 more home runs

than Frank Robinson.

Choose a method to estimate. Then subtract.

1. 
   
   
   
   2. 
      
      
      
      3. 
         
         
         
         4. $ 7.36
            
            4.88
         
         
         
         
      
      
      
      
   
   
   
   

$ 6.24


 5.75

$ 4.17


 2.38

12

7 2 11

$8.3 1


 7.8 4

$. 4 7

5. 624 6. 930 7. 846 8. 561 9. 734
   
   137
   452
   669
   265
   587

Think

128 is close to 100.

The answer is reasonable.

3.1

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