Mental calculations

Can you work out some different ways to balance this equation?

Have a go at balancing this equation. Can you find different ways of doing it?

Can you match these calculation methods to their visual representations?

Can you put these four calculations into order of difficulty? How did you decide?

Do you agree with Badger's statements? Is Badger's reasoning 'watertight'? Why or why not?

Can you find all the ways to get 15 at the top of this triangle of added numbers?

Roll three dice, then add two numbers and take away the other. What answers could you get?

Can you go through this maze so that the numbers you pass add to exactly 100?

Use the 'double-3 down' dominoes to make a square so that each side has eight dots.

Find at least one way to put in some operation signs to make these digits come to 100.