mathematics

1. mathematics Review of expanded form and regrouping Created by: Tamara V. Russell

2. Lesson Objective Today we will see if you remember how to use expanded form as a strategy for addition.

3. Essential question How do you break apart addends to add thousands, hundreds, tens and then ones?

4. vocabulary • value – this is what a digit is worth based on its place within a number. • expanded form – a way to write a number that shows the values of each digit of a number.

5. review What is the value of the underlined digit? 3 3

6. review What is the value of the underlined digit? 75 5

7. review What is the value of the underlined digit? 475 400

8. review What is the value of the underlined digit? 19,985 10,000

9. Expanded form • Now let’s review writing numbers in expanded form. • Here is an example… 395 = 300 + 90 + 5

10. review • How do you write 281 in expanded form? 281 = 200 + 80 + 1

11. review • How do you write 3,561 in expanded form? 3,561 = 3,000 + 500 + 60 + 1

12. review • How do you write 8,309 in expanded form? 8,309 = 8,000 + 300 + 9

13. review • How do you write 45,897 in expanded form? 45,897 = 40,000 + 5,000 + 800 + 90 + 7

14. Lesson • You can use expanded form as a strategy to add numbers. • For example… 375 = 300 + 70 + 5 123 = 100 + 20 + 2 497 = 400 + 90 + 7

15. Practice • Can you complete the following problem? 412 = 400 _____ + 10 + 2 _____ + = 200 + 80 _____ + 1 _____________________ 281 693 = 600 + 90 + 3

16. Practice • Can you complete the following problem? 223 = 200 _____ + 20 + 3 _____ + = 100 + 50 _____ + 6 _____________________ 156 379 = 300 + 70 + 9

17. Practice • Can you complete the following problem? 560 = 500 _____ + 60 _____ + 0 + = 400 + 10 _____ + 9 419 _____________________ 693 = 900 + 70 + 9

18. practice Time for think, pair, share. First, complete lesson 7.1 on paper. Then work with a partner to share & check your work.

19. regrouping • Sometimes you will need to regroup in order to add. You can still use the expanded form strategy. • For example… 10 235 = 200 + 30 + 5 135 = 100 + 30 + 5 370 = 300 + 60 + 10 70 Take away a ten and then add ten to the tens’ column Ten plus 60 is?

20. regrouping • Let’s try that again…. 10 235 = 200 + 30 + 5 146 = 100 + 40 + 6 381 = 300 + 70+ 11 80 1 Take away a ten and add ten to the tens’ column The answer is…. Ten plus 70 is?

21. regrouping • One more time… 100 10 425 = 400 + 20 + 5 198 = 100 + 90 + 8 623 = 500 + 110+ 13 600 20 3 Take away a hundred and add a hundred to the hundreds’ column. Take away a ten and add ten to the tens’ column The answer is…. Ten plus 110 is?

22. White board practice Use your whiteboards and markers for the next three problems.

23. practice Using the expanded form method, solve the following problem. 421 + 329=

24. practice Using the expanded form method, solve the following problem. 531 + 396=

25. practice Using the expanded form method, solve the following problem. 1,348 + 529=

26. Great Job! Exit ticket: How do you break apart addends to add thousands, hundreds, tens and then ones? Respond on your white board.