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There are to be 6 homes built on a new development site. They could be semi-detached, detached or terraced houses. How many different combinations of these can you find?

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This challenge is to design different step arrangements, which must go along a distance of 6 on the steps and must end up at 6 high.

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Train Carriages

Suppose there is a train with 24 carriages which are going to be put together to make up some new trains. Can you find all the ways that this can be done?

Unit Differences

Stage: 1 Challenge Level: Challenge Level:1

This challenge is about finding the difference between numbers which have the same tens digit.

Here are two examples where I’ve decided to use numbers which have two tens:

The number above is always the difference between the two beneath it.

Can you find different pairs of numbers with a difference of 1 or 2 or 3 or 4 ... and so on?

Can you find more than one way of doing it?