Mental calculations

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

Roll two red dice and a green dice. Add the two numbers on the red dice and take away the number on the green. What are all the different possible answers?

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.

Katie had a pack of 20 cards numbered from 1 to 20. She arranged the cards into 6 unequal piles where each pile added to the same total. What was the total and how could this be done?

Sally and Ben were drawing shapes in chalk on the school playground. Can you work out what shapes each of them drew using the clues?

Tim had nine cards each with a different number from 1 to 9 on it. How could he have put them into three piles so that the total in each pile was 15?

This task combines spatial awareness with addition and multiplication.