Addition and subtraction

In each of these games, you will need a little bit of luck, and your knowledge of place value to develop a winning strategy.

Can you use the clues to complete these 6 by 6 Mathematical Sudokus?

Can you use the clues to complete these 5 by 5 Mathematical Sudokus?

Can you use the clues to complete these 4 by 4 Mathematical Sudokus?

Can you use the clues to complete these 3 by 3 Mathematical Sudokus?

Could Ben have any amount of money between 5p and £2 in his pocket if he has five coins?

Complete the Mathdoku grid using the clues. Can you convince us that the number you have chosen for each square has to be correct?

Take three consecutive numbers and add them together. What do you notice?

The Scot, John Napier, invented these strips about 400 years ago to help calculate multiplication and division. Can you work out how to use Napier's bones to find the answer to these multiplications?