Multiplying and Dividing Decimals by Whole Numbers

1
Multiplying and Dividing Decimals by Whole Numbers

• Lesson 3-6

2
Multiplying by whole numbers

• Multiply decimals as you would whole numbers.
  Then place the decimal point in the product. The
  number of decimal places in the product is equal
  to the sum of the number of decimal places in the
  factors.

3
Example 5.63 x 7
2
4
5.63
two
x
7
1
4
39
.
two
4
Multiplying by 10,100, 1000 ect

• When you multiply by 10, 100, or 1,000, you can
  move the decimal point to the right.
• The number of decimal places you move is the same
  as the number of zeroes you are multiplying by.
• When you divide by 10, 100, or 1,000, you can
  move the decimal point to the left. Move the
  decimal point once for each zero you are dividing
  by.

5
1.492 x 100
Move the decimal to the right two spaces.
149.2
6
2,124.94 1,000
Move the decimal to the left three spaces.
2.12494
7
4.2 100
Move the decimal point to the left two spaces.
Add a zero for the second space.
.042
8
15.36 x 1,000
Move the decimal point to the right three
spaces. Add a zero for the third space.
15,360
9
Practice P165 1-9 odd (check answers in back
of text)
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