1. Rounding Decimals Review and Multiplying Decimals
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Rounding Review
Decimals are read as “and”
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Thousandths
Thousands
Ones
Hundredths
Hundreds
Tens
Tenths
Ten Thousandths
Read as 518 and 21 hundredths
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Rounding Review
Find the number. Circle it.
Look next door.
4 or less just ignore.
5 or more add one more.
Example: Round 5368 to nearest hundreds.
Circle the 3 in the hundreds place.
Look next door at the 6.
It is 5 or more so add 1 more to the hundreds place.
5368 rounds to 5400
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Rounding Review
Round to the nearest tenths
Round to the nearest hundredths
2.876
2.9
31.70
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Rounding Review
Round to the nearest tenths
Round to the nearest hundredths
3.478
3.5
22.60
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Multiplying Decimals
Steps for Multiplying Decimals
Step 1: Write the problem vertically.
Step 2: Ignore the decimal point(s) and multiply.
Step 3: Determine where the decimal point goes in the product.
Place the decimal point in the answer by counting how many places the decimal point has moved.
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Multiplying Decimals
Multiply 3 x 0.14 =
0.42
0.14
3 x 0.14
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Multiplying Decimals
Multiply 3 x 0.14 1
Step 1: Write the problem vertically
0.14 x
Step 2: Ignore the decimal points and multiply 4 2
Step 3: Determine where the decimal
point goes in the product.
0.42
The decimal moves two places to the left
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Multiplying Decimals
Multiply 5 x 0.18 =
0.90
5 x 0.18
0.18
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Multiplying Decimals
Multiply 5 x 0.18 4
Step 1: Write the problem vertically
0.18 x
Step 2: Ignore the decimal points and multiply 9
Step 3: Determine where the decimal
point goes in the product.
0.90
The decimal moves two places to the left
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Multiplying Decimals
Multiply 0.2 x 0.6 =
0.2
0.6
0.2
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Multiplying Decimals
Multiply 0.2 x 0.6 =
0.2
x 0.6
0.6
0.2
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Multiplying Decimals
Multiply 0.2 x 0.6 =
0.2 x 0.6
0.6
0.2
= 0.12
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Multiplying Decimals
Multiply 0.2 x 0.6
Step 1: Write the problem vertically
0.2
x 0.6
Step 2: Ignore the decimal points and multiply 1 2
Step 3: Determine where the decimal
point goes in the product.
0. 12
The decimal moves two places to the left
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Multiplying Decimals
Multiply 0.4 x 0.7 =
0.4
0.7
0.4
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Multiplying Decimals
Multiply 0.4 x 0.7 =
0.7
0.4
0.4
x 0.7
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Multiplying Decimals
Multiply 0.4 x 0.7 =
0.7
0.28
0.4
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Multiplying Decimals
Multiply 0.4 x 0.7
Step 1: Write the problem vertically
0.4
x 0.7
Step 2: Ignore the decimal points and multiply 2 8
Step 3: Determine where the decimal
point goes in the product.
0. 28
The decimal moves two places to the left
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Multiplying Decimals
200
Move the decimal two places
to the left in your answer.
x . 25 1 + 4 .
5000
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Multiplying Decimals
HOW MANY DECIMAL PLACES?
1) 3.1(0.28)
3.1
1 decimal place 
2 decimal places
0.868
1 + 2 = 3 decimal places
2) (0.4)(2.53)
0.4
1 decimal place
 2.53
2 decimal places
1.012
1 + 2 = 3 decimal places
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Multiplying Decimals 1 2 1 1) 1
0.16
x 30 2) 70
x 1.2 3)
0.0048
x 32 1 4 1 9 6 4 8 + 7 1 4 4 4 8 8 4 1 5 3 6
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Evaluate The Power
An exponent tells how many times a
number is multiplied by itself. 4 3
Exponent
Base 4
3 is written as 3 • 3 • 3 • 3 = 81
This exponent is read three to the fourth power.
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Evaluate The Power
Evaluate (0.2)2
This means (0.2)(0.2)
0.2
x 0.2 4
0. 04
The decimal goes moves two places to the left
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24. Calculate Area With Decimals
Area = base x height
0.58 in.
Multiply 4 x 0.58
4 in. 3 2
The decimal moves two places to the left.
0.58 x
Area is square units! 2 3 2
2.32 in2
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THE END!!!
Take out your study guide
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26. Multiplying Decimals Multiply 0.4 x 0.14 0.056#5
Multiply 0.4 x 0.14 1
0.14 x
Step 1: Write the problem vertically
Step 2: Ignore the decimal points and multiply 5 6
Step 3: Determine where the decimal
point goes in the product.
0.056
The decimal moves 3 places to the left.

27. The decimal moves two places to the left.
Evaluate The Power #6
Evaluate (0.5)2
This means (0.5)(0.5) 2
0.5
x 0.5
The decimal moves two places to the left. 2 5
0. 25

28. Calculate Area With Decimals
# 7
Calculate Area With Decimals
The Area (A) is the number of square units needed to cover a figure.
0.98 in
Area = base x height
2 in.
Multiply 2 x 0.98 1 1
The decimal moves two places to the left.
0.98 x 1 9 6
Area is square units!
1.96 in2