Cuisenaire rod equations

We've been using letters instead of numbers. All thee Cuisenaire rods have different letter names:

So, looking at some good examples from Annie, seven lots of g is the same length as seven lots of r plus seven lots of w. Or in letters:

7g = 7r + 7w

The two lines are the same length, so the two rows of rods are equal.

We made our own pairs of lines of rods.

 

Later on 4G tried a pair of squares like this.

4B built on top of theirs like this.

 

And we even tried cubes!

 

Here is James P's cube and the algebra to go with it:

 

 

Have a look at a slideshow of our work.

Puzzle based on balanced equation

Solve this:

Anne buys two melons from the market which are weighed by the seller as shown below: How much did the two pieces of melons weigh together?

Balanced equations

On Monday we looked at balanced equations using the number scales.  Like this one:

 10 + 8 + 6 + 4 + 2  = 30 =  (5 x 2) + (4 x 2) + (3 x 2) + (2 x 2) + (1 x 2)

Can you say what the equation would be for any of these balances?

A.

B.

C.

You could post your equations in the comments below.