Post on 16-Jun-2020
Lesson 9 Sums and Differences of Decimals.notebook
1
December 03, 2013
I will use my knowledge of adding and subtracting multidigit numbers to find the sums and differences of decimals.
Today's Objective:
Lesson 9 Sums and Differences of Decimals.notebook
2
December 03, 2013
Example 1:
25 376 3 10
77 100+
Example 2:
426 27515
12
Review adding fractions
Lesson 9 Sums and Differences of Decimals.notebook
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December 03, 2013
When do you think it might be easier to convert a mixed number to a decimal before adding or subtracting them?
Lesson 9 Sums and Differences of Decimals.notebook
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December 03, 2013
Place Value
Lesson 9 Sums and Differences of Decimals.notebook
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December 03, 2013
I DO:
4261
5275 1
2
Lesson 9 Sums and Differences of Decimals.notebook
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December 03, 2013
WE DO
Lesson 9 Sums and Differences of Decimals.notebook
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December 03, 2013
YOU DO
Lesson 9 Sums and Differences of Decimals.notebook
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December 03, 2013
YOU DO
Lesson 9 Sums and Differences of Decimals.notebook
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December 03, 2013
Use a calculator to convert the fractions into decimals before calculating the sum or difference.
5. Rahzel wants to determine how much gasoline he and his wife use in a month. He calculated that he used 78 gallons of gas last month. Rahzel’s wife used 41 gallons of gas last month. How much total gas did Rahzel and his wife use last month? Round your answer to the nearest hundredth.
Expression: Estimated answer:
Actual answer:
38
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Lesson 9 Sums and Differences of Decimals.notebook
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December 03, 2013
Closing:
* Let's share answers and processes for each of the exercise problems.
* Which exercises would be easiest if the addends, minuends, or subtrahends were converted to decimals.
Lesson 9 Sums and Differences of Decimals.notebook
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December 03, 2013
Exit Ticket:
Solve each problem. Show the placement of the decimal is correct through either estimation or fraction multiplication.
1. 382 − 191
2. 594 + 893
87 100
3 10
7 25
71 100