Cuisenaire Counting printable sheet

I have some rods that are different colours and different lengths.

I can arrange white and red rods in many different ways to be the same length as a yellow rod. Here are some of them:

 

Can you find all the ways of using red and white rods that are equivalent to a yellow rod?

How will you know that you haven't missed any out?

You could use the interactivity below to try out your ideas.

The dark green rod is longer than the yellow rod.
Can you find all the ways of using red and white rods that are equivalent to a dark green rod?
How will you know that you have found them all?