Solve Problems Involving Two Ratios

In this activity, we will use what we know about ratio to solve some problems involving two ratios.

 

Example

In a jar there are green, red and yellow sweets.

The ratio of green to red is 3:1

The ratio of red to yellow is  2:5

Find the ratio of green: red: yellow

 

 

Answer

Firstly, we cannot just put them together.

They need to be in the same proportions.

That means, the one that links them has to be the same - confused?

Let's do it and it will help

 

Write them out as we have them:

 

 

We need the red to be the same because it is in both ratios.

So if we multiply 3:1 by 2 = 6:2 the two ratios are proportional.

 

 

The ratio of green:red:yellow = 6:2:5

 

Does that make sense?

 

Let's practise these!