Multiply Decimals by
Powers of 10
Estimate Multiplication with Decimals
Model Multiplication with Decimals
Decimals by Whole Numbers
(Mental Math)
Multiply Decimals by
Whole Numbers
200

Adam is laying ceramic tile on a kitchen floor. 

Each tile costs $3.59. How much do 100 tiles cost?

$359

200

Estimate

5.95 x 3.88

5.95 x 3.88
     6 x 4
About 24

200

Write an equation for the multiplication decimal model shown

0.25 x 2 = 0.50

200

8 x 0.9 = 

7.2

Seven and two tenths

200

83.5 x 6

83.5 x 6 = 501.0

400

A packet of ketchup has 0.45 fluid ounces of liquid. How much liquid is in 102 packets of ketchup

45 fl oz

400

Jeremiah buys 42 Air Heads that cost $0.19 each.

What is the best estimate for how much his total is?

40 x $0.20 = $8.00

His total is about $8.00

400

Write an equation for the multiplication decimal model shown

0.8 x 3 = 2.4

400

0.6 x 0.03 = 

0.018

Eighteen Thousandths

400

Levi buys 42 Air Heads that cost $0.19 each.

What is his actual total?

$7.98

600

What power of 10 makes the equation true?

0.305 x ___ = 3,050

104 

600

Estimate

0.5 x 41.07

0.5 x41.07
0.5 x 40
"1/2 of 40"
About 20

600

Write an equation for the decimal model shown

0.7 x 0.4 = 0.28

-or-

0.4 x 0.7 = 0.28

600

80 x 0.4 =

80 x 0.4 = 32.0 = 32

600

One gallon of milk has 128 fluid ounces. How much milk is in 8.5 gallons?

1,088 fl oz

800

Savannah bought seashells from the souvenir shop when she was on vacation. Each seashell cost $0.85

How much would it be if she wanted to buy 10 seashells?

How much would it be if she wanted to buy 100 seashells?

10 for $8.50 

100 for $85

800

Estimate

389.945 x 38.894

389.945 x 38.894
400 x 40
About 16,000

800

Write an equation for the decimal multiplication model


0.8 x 0.4 = 0.32

-or-

0.4 x 0.8 = 0.32

800

1.2 x 0.4

0.48

800

46.9 x 30 =

46.9 x 30 = 1,407.0

1000

The decimal point moves   ________ spot  to the      _______  for every power of 10. 


The decimal point moves  ONE spot to the     RIGHT  for every power of 10. 

1000

Without doing the multiplication, drag the numbers to match each expression with its product.
Use estimation and number sense to help you.

20.397        11.04           49.9125

9.2 x 1.2

5.23 x 3.9

6.05 x 8.25

9.2 x 1.2 = 11.04
9x1=9 

5.23 x 3.9 = 20.397
5x4=20 

6.05 x 8.25 = 49.9125
6x8=48

1000

Write an equation for the decimal multiplication model


0.2 x 0.5 = 0.10 = 0.1

-or-

0.5 x 0.2 = 0.10 = 0.1

1000

900 x 0.01 = 

900 x 0.01 = 9.00

1000

2.73 x 44 = 

2.73 x 44 = 120.12

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