Factors and multiples

problem
Digit discovery

Age

7 to 11

Challenge level

Here is an interesting property about two sets of digits. Can you work out what the digits might be?
problem
Xavi's T-shirt

Age

7 to 16

Challenge level

How much can you read into a T-shirt?
problem
What numbers can we make now?

Age

11 to 14

Challenge level

Imagine we have four bags containing numbers from a sequence. What numbers can we make now?
page
Mathdoku demonstration

This video of Charlie and Liz solving a 6 by 6 Mathdoku may give you ideas for strategies to try.
problem
6 by 6 Mathdokus

Age

7 to 16

Challenge level

Can you use the clues to complete these 6 by 6 Mathematical Sudokus?
problem
5 by 5 Mathdokus

Age

7 to 16

Challenge level

Can you use the clues to complete these 5 by 5 Mathematical Sudokus?
problem
4 by 4 Mathdokus

Age

7 to 14

Challenge level

Can you use the clues to complete these 4 by 4 Mathematical Sudokus?
problem
3 by 3 Mathdokus

Age

7 to 14

Challenge level

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

Celebrate 25 years of NRICH

Age

5 to 14

To celebrate NRICH's 25th birthday, why not play this special version of our classic game, Got It? Can you devise a strategy so that you will always win?
problem
Mathdoku

Age

7 to 11

Challenge level

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