Today we will compute simple division of fractions.

1. Today we will compute simple division of fractions. Compute= calculate or work out But First let’s review what we’ve already learned!

2. Remember that when multiplying fractions • When multiplying fractions, they do NOT need to have a common denominator. • To multiply two (or more) fractions, multiply across, numerator by numerator and denominator by denominator. • If the answer can be simplified, then simplify it. • Example: • Example:

3. Equivalent Fractions • Name the same amount but have different numerators and denominators. 1 2 1 1 = 4 2 4 2 1 4

4. Equivalent Fractions • Are sometimes called equal fractions: two or more fractions that name the same number. 1 2 1 1 = 4 2 4 2 1 4

5. Equivalent Fraction Models 1 2 3 = = 2 4 6

6. Simplifying Reduce = = = 10 = Greatest Common Factor Write the numerator and denominator as a product of factors, then cancel common factors and obtain the result.

7. Simplifying = = = = Write the numerator and denominator as a product of common factors then cancel the common factors and obtain the result. Repeat the simplification process until all common factors are removed.

8. Converting Mixed Numbers 1 1 5 5 3 3 3 3 + 16 = 3 Multiply the whole number by the denominator Add the numerator to the result Place over the initial denominator Compute the final result

9. Converting Mixed Numbers 2 2 6 6 9 9 9 9 + 56 = 9 Multiply the whole number by the denominator Add the numerator to the result Place over the initial denominator Compute the final result

10. Dividing Fractions 31 ? 4 8 : = Let’s think about what dividing fractions means. In this expression it means “How many one eighths are in three fourths?” For example, how many one eighth slices of pizza are in three fourths of a pizza?

11. 31 4 8 31 4 8 : = 6 : = ? How many one eighths are in three fourths? To find this we must first find 3/4 of the pizza. We then cut each fourth into halves to make eighths. We can see there are 6 eighths in three fourths.

12. 11 ? 2 8 11 2 8 : = : = 4 EXAMPLE 1: How many one eighths are in one half? Using a fraction manipulative, we show one half of a circle. To find how many one eighths are in one half, we cover the one half with eighths and count how many we use. We find there are 4. There are four one eighths in one half.

13. Change Operation. Flip 2nd Fraction. Dividing Fractions • When dividing fractions, they do NOT need to have a common denominator. • To divide two fractions, change the operation to multiply and take the reciprocal of the second fraction (flip the second fraction). Keep-Change-Change.

14. Dividing Fractions • Finish the problem by following the rules for multiplying fractions.

15. Dividing Fractions Ex) Divide.

16. Dividing Fractions Ex) Divide.

17. Dividing Fractions Ex) Divide. Invert and Multiply !

18. Dividing Fractions Ex) Divide. 15 and 5 have a common factor.

19. Dividing Fractions Ex) Divide. Divide them both by 5.

20. Dividing Fractions Ex) Divide.

21. Dividing Fractions Ex) Divide. 22 and 6 have a common factor.

22. Dividing Fractions Ex) Divide. Divide them both by 2.

23. Dividing Fractions Ex) Divide. Divide them both by 2.

24. Dividing Fractions Ex) Divide.

25. Dividing Fractions Ex) Divide.

26. It is important to know how to compute simple division of fractions because... • You will need to know it for 7th grade math! • You will need it for the CST’s! • Why else is it important?

27. What we’ve learned! • How do you reduced fractions? Do you use the LCM or the GCF? • What does compute mean? • What happens if you need to multiply or divide fractions and the number is mixed?