# Something in Common: Number

This sub-collection of resources from the ‘Something in Common’ collection contains three resources designed to bring a problem solving approach to the teaching of number in Key Stage 3. Each problem comes with several different versions of a problem that have ‘something in common’. Having discovered the ‘something in common’ the challenge is to understand the underlying mathematics that gives these results.

## Resources

### Magic Fractions

Three distinct non-zero integers are chosen such that their sum is equal to zero. From the three numbers all six possible ordered pairs are formed. Each ordered pair is then turned into a...

### Cross Bear!

This problem is an interesting variation on ‘Goldilocks and the Three Bears’. All three bears start eating their porridge at the same time but at different rates. The time is given for Daddy...

### Piscatorial Percentages

The number of fish in a tank is given, together with the percentage of the fish that are small. The challenge is to work out the number of the small fish to remove to achieve a lower given...