Lesson 9.8: Multiplication of Decimals

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Lesson 9.8Multiplication of Decimals
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(No Transcript)
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Mental Mathestimate the product and write the
number model you used to solve it
Example 9 18 You write 9 20
180 or 10 18 180
11 42
28 49
22 76
63 63
98 59
72 414
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Math Message

• Solve the problem at the top of MJ page 268

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Estimating Products of Decimals

• We will learn to find the product of decimals

On your slate, estimate each product. Show your
work.
11 2.8
110 2.8
11 0.28
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Which problem is most likely to have the product
30.8? How do you know?
110 2.8
11 0.28
11 2.8
110 2.8
308
Where would you place the decimal point? How do
you know?
11 0.28
308
Where would you place the decimal point? How do
you know?
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Estimate the cost of 5 calculators
Multiply 5 929
Lets use our estimate to place the decimal.
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What are the steps to estimating the product of
decimals?
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Partnership Work MJ p 268
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Math Journal page 269
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What did we learn