1. Evaluate each expression if a = 3, b = 7, and c = 2. 4. 5. 6.
Divide.
1. 64 ÷ (–8)
2. –45 ÷ (–15) 3.
Evaluate each expression if a = 3, b = 7, and c = 2. 4. 5. 6.
7. Stock prices fell 250 points one day and 60 points the next day. What is the average change in stock prices over the two days?
Course 2, Lesson 4-1

2. ANSWERS
1. −8
2. 3
3. −30
4. −6
5. 14
6. 4.5
7. –155
Course 2, Lesson 4-1

3. WHAT happens when you add, subtract, multiply, and divide fractions?
The Number System
WHAT happens when you add,
subtract, multiply, and divide fractions?
Course 2, Lesson 4-1

4. The Number System
7.NS.2
Apply and extend previous understandings of multiplication and division and of fractions to multiply and divide rational numbers.
7.NS.2d
Convert a rational number to a decimal using long division; know that the decimal form of a rational number terminates in 0s or eventually repeats.
7.EE.3
Solve multi-step real-life and mathematical problems posed with positive and negative rational numbers in any form (whole numbers, fractions, and decimals), using tools strategically. Apply properties of operations to calculate with numbers in any form; convert between forms as appropriate; and assess the reasonableness of answers using mental computation and estimation strategies.
Course 2, Lesson Common Core State Standards © Copyright National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.

5. Mathematical Practices
The Number System
Mathematical Practices
1 Make sense of problems and persevere in solving them.
3 Construct viable arguments and critique the reasoning of others.
4 Model with mathematics.
6 Attend to precision.
7 Look for and make use of structure.
Course 2, Lesson Common Core State Standards © Copyright National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.

6. To write fractions as decimals To write decimals as fractions
The Number System
To write fractions as decimals
To write decimals as fractions
Course 2, Lesson 4-1

7. repeating decimal bar notation terminating decimal
The Number System
repeating decimal
bar notation
terminating decimal
Course 2, Lesson 4-1

8. Example #1
Course 2, Lesson 4-2

9. Another Example:
Course 2, Lesson 4-2

10. Example #2
Course 2, Lesson 4-2

11. Another Example:
Course 2, Lesson 4-2

12. Example #3
Course 2, Lesson 4-2

13. Another Example:
Course 2, Lesson 4-2

14. Got it?
Course 2, Lesson 4-2

15. Example #4
Course 2, Lesson 4-2

16. Another Example:
Course 2, Lesson 4-2

17. Example #5
Course 2, Lesson 4-2

18. Another Example:
Course 2, Lesson 4-2

19. Example #6
Course 2, Lesson 4-2

20. Another Example
Course 2, Lesson 4-2

21. Got it?
Course 2, Lesson 4-2

22. Example #7
Course 2, Lesson 4-2

23. Another Example:
Course 2, Lesson 4-2

24. Got it?
Course 2, Lesson 4-2

25. How did what you learned today help you answer the
The Number System
How did what you learned
today help you answer the
WHAT happens when you add,
subtract, multiply, and divide fractions?
Course 2, Lesson 4-1

26. How did what you learned today help you answer the
The Number System
How did what you learned
today help you answer the
WHAT happens when you add,
subtract, multiply, and divide fractions?
Sample answers:
Fractions and mixed numbers can be written as decimals. The decimal is either a terminating or repeating decimal.
Course 2, Lesson 4-1

27. The Number System
Ratios and Proportional Relationships
The next lesson is about comparing and ordering rational numbers. How do you think what you learned in this lesson will connect with the next lesson?
Course 2, Lesson 4-1