Lesson 2

• Mathematics
• Lower Secondary (Key Stage 3)

Lesson 2

Describe what a bar model is and how it can be used to show ratios.

Select the correct bar model for the ratio blue : brown = 3 : 4

1. 
2. 
3. 
4. 

Simplify the ratio in the bar model below in terms of blue to brown:

1. 4 : 8
2. 8 : 4
3. 1 : 2
4. 2 : 1

Select the equivalent bar model for the ratio blue : brown = 1 : 1

1. 
2. 
3. 
4. 

Select the correct fraction for the bar model below in the form blue/brown:

1. 3/8
2. 3/5
3. 5/8
4. 8/5

Select the correct fraction for the bar model below in the form brown/whole:

1. 3/8
2. 8/3
3. 8/5
4. 5/8

Match the correct ratio to the bar model.  (NOTE: each ratio is blue:brown)

1 : 1

4 : 3

3 : 5

3 : 4

Starter

Calculate the following expressions:

          

3 + 4 x 5	3 x 4 + 5	3 x (4 + 5)	3 x 4 + 4 x 5
18 ÷ 2 + 6	18 ÷ 6 - 2	18 ÷ (3 + 6)	18 ÷ 3 + 13

3/8 of the purple paint is made up of red paint.

5/8 of the purple paint is made up of blue paint.

The amount of red paint used is 3/5 of the amount of blue paint used .

The amount of blue paint used is 5/3 of the amount of red paint used .

1. 2/7
2. 2/9
3. 7/9
4. 7/2

1. 2/7
2. 2/9
3. 7/9
4. 7/2

1. 2/7
2. 2/9
3. 7/9
4. 7/2

?

2/5

?

3/5

3/5