d) Multiply Decimals

8/22/2019 d) Multiply Decimals

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copyrightamberpasillas2010

DECIMALSRounding Decimals Review

andMultiplying Decimals


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___ , ___ ___ ___ ___ ___ ___ ___

Thousands

Hu

ndreds

Tens

Ones

Tenths

Hundredths

Thou

sandths

TenThousandths

5 1 8 2 1

Read as 518 and 21 hundredths

Decimals are read as and

Rounding Review


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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

Rounding Review


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Round to the

nearesttenths

2.876

2.9

Round to the

nearest hundredths

31.6999

31.70

Rounding Review


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Round to thenearest tenths

3.478

3.5

Round to thenearest hundredths

22.5972

22.60

Rounding Review


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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 pointgoes in the product.

Place the decimal point in the answerby counting how many places thedecimal point has moved.

Multiplying Decimal


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Multiply 3 x 0.14

0.14 3 x 0.14

=

0.42

Multiplying Decimal


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Multiply 3 x 0.14

2

Step 1: Write the problem vertically0.14

x 3 Step 2: Ignore the decimal pointsand multiply

Step 3: Determine where the decimal

point goes in the product.

The decimal moves two placesto the left

1

40

0.42

Multiplying Decimal


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Multiply 5 x 0.18

0.18 5 x 0.18

=

0.90

Multiplying Decimal


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Multiply 5 x 0.18

0


x 5 Step 2: Ignore the decimal pointsand multiply



The decimal moves two places to the left

4

90

0.90

Multiplying Decimal


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Multiply 0.2 x 0.6

0.2 0.6

=

0.2

Multiplying Decimal


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Multiply 0.2 x 0.6

0.2 0.6

=

0.2 x 0.6

Multiplying Decimal


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Multiply 0.2 x 0.6

0.2 0.6

=

0.2 x 0.6

= 0.12

Multiplying Decimal


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Multiply 0.2 x 0.6

2


x 0.6 Step 2: Ignore the decimal pointsand multiply




10

0. 12

Multiplying Decimal


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Multiply 0.4 x 0.7

0.4 0.7

=

0.4

Multiplying Decimal


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Multiply 0.4 x 0.7

0.4 0.7

=

0.4 x 0.7

Multiplying Decimal


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Multiply 0.4 x 0.7

0.4 0.7

=

0.28

Multiplying Decimal


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Multiply 0.4 x 0.7

8


x 0.7 Step 2: Ignore the decimal pointsand multiply




20

0. 28

Multiplying Decimal


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Multiplying Decimal200

x .250+

5000

0001 004

Move thedecimaltwo placesto the left inyour answer.

.


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Multiplying DecimalHOW MANY DECIMAL PLACES?

1 decimal place3.1

2) (0.4)(2.53)

0.4 2.53

1) 3.1(0.28)

1.012

0.28 2 decimal places0.868 1 + 2 = 3 decimal places

1 decimal place2 decimal places

1 + 2 = 3 decimal places


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Multiplying Decimal1) 0.16

x 30

000 084084

12) 70

x 1.2

041 007048

+

3)

1

0.0048

x 32

690 044635

1

11

2

0

0

1

0


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Evaluate The Power

Anexponent

tells how many times anumber is multiplied by itself.

34

BaseExponent

3 is written as 3 3 3 3 = 814

This exponent is read three to the fourth power.


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Evaluate The Power

Evaluate (0.2)2

4

This means (0.2)(0.2)0.2

x 0.2

The decimal goes moves two places to the left

00

0. 04


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Calculate Area With Decimals

4 in.

0.58in. Area = base x heightMultiply 4 x 0.58

2

0.58

x 4

The decimalmoves two

places to the

left.

3

32

2.32 in2

2

Area is

square units!


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THE END!!!Take out your study guide


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Multiply 0.4 x 0.14

6


x 0.4Step 2: Ignore the decimal points

and multiply



The decimal moves3 placesto theleft.

1

50

0.056

Multiplying Decimals#5

0


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Evaluate The Power

Evaluate (0.5)

2

5

This means (0.5)(0.5)

0.5

x 0.5The decimalmoves two

places to the left. 20

0. 25

#6

2


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2 in.

0.98 in Area = base x height

# 7

Multiply 2 x 0.98

6

0.98

x 2

The decimal

moves two

places to theleft.

1

91

1.96 in2

1

Area is

square units!

TheArea(A)is the number ofsquare units

needed to cover a figure.

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d) Multiply Decimals