Addition and subtraction

problem

A-Magical Number Maze

Age

7 to 11

Challenge level

This magic square has operations written in it, to make it into a maze. Start wherever you like, go through every cell and go out a total of 15!
problem

Buckets of Thinking

Age

7 to 11

Challenge level

There are three buckets each of which holds a maximum of 5 litres. Use the clues to work out how much liquid there is in each bucket.
problem

Sept03 Sept03 Sept03

Age

7 to 11

Challenge level

This number has 903 digits. What is the sum of all 903 digits?
problem

The Number Crunching Machine

Age

7 to 11

Challenge level

Put a number at the top of the machine and collect a number at the bottom. What do you get? Which numbers get back to themselves?
problem

Magic Triangle

Age

7 to 11

Challenge level

Place the digits 1 to 9 into the circles so that each side of the triangle adds to the same total.
problem

The Pied Piper of Hamelin

Age

7 to 11

Challenge level

This problem is based on the story of the Pied Piper of Hamelin. Investigate the different numbers of people and rats there could have been if you know how many legs there are altogether!
problem

Adding Plus

Age

7 to 11

Challenge level

Can you put plus signs in so this is true? 1 2 3 4 5 6 7 8 9 = 99 How many ways can you do it?
problem

Cherries Come in Twos

Age

7 to 11

Challenge level

Susie took cherries out of a bowl by following a certain pattern. How many cherries had there been in the bowl to start with if she was left with 14 single ones?
problem

Numbered Cars

Age

7 to 11

Challenge level

Can you crack my code and use it to find out what two car number plates add up to?
problem

All Seated

Age

7 to 11

Challenge level

Look carefully at the numbers. What do you notice? Can you make another square using the numbers 1 to 16, that displays the same properties?