The document provides instructions and examples for adding and subtracting fractions with unlike denominators. It explains that to add or subtract unlike fractions, they must first be rewritten as equivalent fractions with a common denominator, which can be any common denominator or the least common denominator. It then provides examples of finding the least common denominator and rewriting fractions with a common denominator before adding or subtracting them. The document concludes by providing 8 practice problems for students to complete.

1. Friday, October 14 th Please write down Homework and complete Warm UP Simplify 9 + (-10) – 21 Simplify -24 – (-27) x (-2)

2. Decimal Packet + and – due next Wednesday x and ÷ due next Friday WHY? Our next unit is rational numbers…decimals, fractions, negatives, positives

3. Subtracting decimals Adding Decimals *When you subtract decimals you have to: line up your decimals and add in your zeroes *Remember that every number is a decimal, even if a decimal point isn’t written. Example: 5 is really 5.0

4. A little Riddle…. “ Line up your decimals, add in your zeroes, find the sum, don’t be a bum…..line up your decimals, add in your zeroes, now it’s time to subtract, don’t get this out of wack”

5. Unit #1 Fractions +, -, x, and ÷

6. + and - Rule When you add and subtract fractions they must have the same denominator You only add or subtract the Numerator

7. Review: Simplest Form Your answers always must be in simplest form Simplest form=no common factors Think? Can I divide both numbers by anything? Example: 8/14 Can I divide 8 or 14 by anything? 2 So 4/7

8. Homework Answers

9. Todays Mission Adding and subtracting with unlike denominators

10. How do we add when we don’t have common denominators?!?

12. Fractions that represent the same value are equivalent. Remember! To add or subtract unlike fractions, first rewrite them as equivalent fractions with a common denominator.

13. You can use any common denominator or the least common denominator to add and subtract unlike fractions. The least common denominator (LCD) is the least common multiple of the denominators.

14. – – Multiples of 8: 8, 16, 24, … The LCD is 24. Write equivalent fractions with a common denominator. Subtract. Multiples of 12: 12, 24, … 11 12 __ 3 8 __ 11 12 __ 3 8 __ 22 24 __ 9 24 __ 13 24 __

15. – – Multiples of 3: 3, 6, 9, 12, 15, 18, 21, … The LCD is 21. Write equivalent fractions. Subtract. Multiples of 7: 7, 14, 21, … 4 7 __ 1 3 __ 4 7 __ 1 3 __ 12 21 __ 7 21 __ 5 21 __

16. Add or subtract. Write each answer in simplest form. 1. + 2. – 3. – 4. + 5. Bonnie is making oatmeal bars and the recipes calls for cup of brown sugar. If she has cup of brown sugar, how much more does she need? 3 8 __ 1 6 __ 1 2 __ 1 8 __ 5 12 __ 1 6 __ 1 6 __ 1 8 __ 3 4 __ 1 3 __ 13 24 __ 3 8 __ 1 4 __ 7 24 __ 5 12 __ cup

17. You Try Complete all 8 problems on your notes When you are done, raise your hand and then help others around you 