Grade 4 - Progress in Mathematics

Products: Rounding to Estimate

4-11

A school bought 28 cans of paint for a special

school project. The school bought the paint

at a discounted price of $5.25 per can. About

how much money did the school spend on paint?

To find about how much the school spent,

estimate: 28 
$ 5.25

Rounding is one way to estimate products:


Round each factor to its greatest place.


Multiply.

$ 5.25 $ 5. 00


 28 
 30

about $ 150. 00

The school spent about $150 on 28 cans of paint.

Study these examples.

43 40 586 600 $ .48 $ .50


 62 
 60 
 55 
 60 
 32 
 30

about 2400 about 36,000 about $15.00

Yo u can write $150.00 as $150.

Estimate each product by rounding.

1. 52 2. 68 3. 91 4. 86 5. 47
   
   75
   41
   22
   57
   33


2. 19 7. 78 8. 29 9. 34 10. 85
   
   62
   53
   58
   92
   38


3. $ .17 12. $ .36 13. $ .42 14. $ .66 15. $ .26
   
   27
   81
   74
   65
   57

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