Description of Lesson:
- Orientation [5 mins]- There are three types of fractions: proper fraction (3/4), improper fraction (7/4) and mixed fraction (1 ¾). Teacher-How to add, subtract, multiply and divide with fractions?
- Introduction [10 mins] – Before solving any problem with rational numbers, finding a common denominator is necessary but some best common denominator is not that obviously. For example, (5/6)-(3/8)=? The common denominator could 48 but 6 and 8 share a common factor 2. Thus, 48/2=24 is the best common denominator for this problem. The answer is (5/6)-(3/8)=(20/24)-(9/24)=11/24. Simplest form, to remove the same factors form the terms of a fraction, is also important in order of operation within rational numbers. For example, (15+9)/6=24/6=4/1=4. There is one more example.
Discuss: (15+9)/(15-3), 5+(18-12)/6, 5+(18/6)-12.
- Activity 1 [20 mins] – Blocks model- Teacher to walk around the room to be of assistance during the activity.
- Material
Worksheets
Markers (Yellow, red, blue, brown, green)
Each students will get three pieces of worksheet. They will color the area of pattern blocks to represent the mixed numbers in problem questions. Then write down the answer. Students will use pattern blocks to model positive mixed numbers and the sums and differences of positive mixed numbers. Students will understand subtraction of mixed numbers as adding the additive inverse.
- Activity 2 [10 mins] – Online Game (4 people as a group)
http://www.mathgametime.com/games/speedway-add-subtract-fractions