Day 56 Numeracy (Ratio and Proportion)

Ratio and Proportion

Ratio

In our class of 16 students, 6 of them are male and 10 are female. We can express this as a ratio in three different ways:

1. 6:10
2. 6/10
3. 6 to 10

Proportion

Students will be given Janet's bannock recipe:

Jan's Bannock Recipe

1. 8 cups of flour
2. 4 tblsps of baking powder
3. 1 1/2 cups of oil
4. 3 tsps salt
5. 5 cups of water

Students will be informed that this recipe will make 3 loaves of bannock./ The question will then be posed, "How much of each ingredient will be need to make 9 loaves? 20 loaves?"

9 Loaves (multiply everything by 3)

1. 24 cups of flour
2. 12 tblsps baking powder
3. 4 1/2 cups oil
4. 3 eggs
5. 15 cups of water

20 Loaves (need to cross multiply)

1. flour: 8/3 = x/20 => 160 = 3x => 53.3 = x Therefore, we need 53 1/3 cups of flour
2. baking powdeer: 4/3 = x/20 => 80 = 3x => 26.6 = x Therefore, we need 26 2/3 tblsps of bp
3. oil: 3/2 / 3 = x/20 => 3/6 = x/20 => 60 = 6x => x = 10 Therefore, we need 10 cups of oil

Students will solve these problems and then complete the exercises on Pages 50 - 52 of Mathematics Concepts: Student Workbook.