6th Grade Math Textbook, Progress

9

Operations V

Multiply 1- and 2-Digit Numbers

Multiply: 7
 27 .

First estimate by rounding: 7 
 30 210.

Then multiply.

To multiply by a one-digit number:

Multiply the ones. Multiply the tens.

Then regroup. Then regroup.

44


 27 
3 2 7


 7 
 337


 9 
 189

The product is 189.

?

Think

189 is close to the

estimate of 210.

Think

1472 is close to the

estimate of 1500.

Multiply: 32
 46 .

First estimate by rounding: 30
 50 1500.

Then multiply.

To multiply by a two-digit number:

Add the

Multiply Multiply partial

the ones. the tens. products.

 46 46 46


 3 2 
 32 
 32


 92 2 
 46 9 2 92 partial

1380 30 
 46  1380 products

1472

The product is 1472.

?

Estimate by rounding. Then find the poduct.

1.  55 2.  613 3. 7
   $8.64 4. 67 5. 329 6. 92
   $7.68
   
   6
   9
   34
   43

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