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Extensions |
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In Example A, Tran used compatible numbers to
find that
300 + 1,800 + 4,700 = 6,800. Here's why it works. |
| 300 + 1,800 + 4,700 = 300 + 4,700 + 1,800 |
Commutative Property |
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(300 + 4,700) + 1,800 |
Associative Property |
| 5,000 + 1,800 |
Addition |
| 6,800 |
Addition |
| 24. Find 2,600 + 1,900 + 400 by using compatible numbers. Show why it works. |
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| Use the Competition problem for 25–28. |
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Tell what you know in your own words.
Identify key facts and details. |
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| 26. |
Tell what the question is asking. |
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Show the main idea. |
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Solve the problem. |
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| 29. |
8,000 is
the same as 80 ___ . |
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| A. ones |
B. tens |
C. hundreds |
D. thousands |
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Practice Game |
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| Dueling Decimals |
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| Players: 2 |
Materials: 2 number cubes, recording sheet |
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Each player records 2 zeros on any of the six blanks. |
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Players take turns tossing 2 number cubes
and writing the numbers in any of the four
remaining blanks. Players read their
numbers aloud and compare them. |
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| 3. |
The player with the smaller number
wins the round. The first player to
win 5 rounds wins the game.
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All text pages available online and on CD-ROM. |
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