Move the top right-hand corner of the rectangle to see what happens.

**Can you work out what the purple number represents?**

Here are some questions you might like to consider:

**What would be the dimensions of a rectangle with a purple number of 24? Is there more than one?**

**Given the coordinates of the top right-hand corner of the rectangle, is there a quick way to work out the purple number?**

**What other interesting questions are there to explore?**