All scales are balanced - both sides weigh the same.
The first scales tell you how many triangles a circle or a square weighs.
The triangles are missing on the last scale. Write down how many there are.
Example
For parents
What does this exercise practice?
The shape scales practice equation thinking without numbers - the child replaces a shape with what it balances and so combines two scales into one answer.
Common pitfalls
Replace every shape completely - a square that weighs two circles becomes two circles, and each of them becomes its triangles. If the same shape stands on both sides, you can take it off both sides.
How to practice at home
Act it out with building blocks and a coat-hanger scale, finding how many small blocks balance a big one.
Related: The Balance Puzzle