Grade 4 - Progress in Mathematics

Special Factors

4-3

Look for a pattern when you multiply tens.

4 
1 ten 4 tens 7 
1 ten 7 tens

4 
 10  40 7 
 10  70

2 
3 tens 6 tens 2 
5 tens 10 tens

2 
 30  60 2 
 50  100

To multiply tens, hundreds, or thousands:


Multiply the nonzero digits.


Count the number of zeros in the factors.

Then write the same number of zeros in the product.

50 700 5000


 9 1 zero 
 4 2 zeros 
 6 3 zeros

450 2800 30 ,000

Write a multiplication sentence for each.

8 
 10  80

3.2

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