Partial-Products Multiplication

47 * 236 = ?

 

 

Think of 236 as 200 + 30 + 6

Think of 47 as 40 + 7

 

Multiply each part of 236 by 47, first by 40:

 

 

then by 7:

 

 

Add these six partial products:

 

1,000s

100s

10s

1s

 

 

2

3

6

 

 

*

4

7

 

 

 

 

 

40 * 200=

8,

0

0

0

40 * 30 =

1,

2

0

0

40 * 6 =

 

2

4

0

7 * 200 =

1,

4

0

0

7 * 30 =

 

2

1

0

7 * 6 =

 

 

4

2

 

11,

0

9

2

47 * 236 = 11,092

 

 

 

(Donít forget to carry the 1 from the 100s column)

 

 

Partial-Products Multiplication with Decimals

 

4.7 * 2.36

 

1. Count the number of decimal places in each factor.

 

 

1 decimal place in 4.7

2 decimal places in 2.36

2. Add the number of decimal places. This is how many

Decimal places there will be in the product.

1 + 2 = 3 decimal places

3. Multiply the factors as if they were whole numbers:

 

47 * 236 = 11,092 (see above)

4. Start at the right of the product. Move left the number of decimal places that you counted in step (1)

11092. Move the decimal 3 places to the left:

 

11.092

4.7 * 2.36 = 11.092