# Factors and multiples

**250**NRICH Mathematical resources connected to

**Factors and multiples**

problem

Favourite

### What numbers can we make now?

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

Favourite

### 5 by 5 Mathdokus

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

problem

Favourite

### 4 by 4 Mathdokus

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

game

### Celebrate 25 Years of NRICH

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

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

problem

### What does it all add up to?

If you take four consecutive numbers and add them together, the answer will always be even. What else do you notice?