Grade 4 - Progress in Mathematics

Estimate Quotients

12-3

Write the compatible numbers you would use

to estimate the quotient. Then estimate.

1. 63
   21 2. 89
   32 3. 78
   19 4. 47
   22


2. 58
   33 6. 67
   11 7. 81
   44 8. 92
   36


3. 594
   26 10. 905
   38 11. 825
   18 12. 652
   21


4. 452
   17 14. 395
   24 15. 6475
   36 16. 7959
   43

To estimate quotients with 2-digit

divisors, think of nearby numbers

that are compatible.

Estimate using compatible numbers:

664 
 24

664 
 24

600 20

So 664 
24 is about 30.

Study these examples.

Estimate: 96 
 31 Estimate: $ 86.43 
 38

So 96 
31 is about 3. So $ 86.43 
38 is about $ 2.00.

When one number divides

another evenly, the two

numbers are compatible.

30

Think: 20
 6  0  0 

Compatible numbers

Think

3

30 
 9  0 

Think

$ 8 2.00

40 
$ 80 .0 0 

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