 This is a mathematical snack from the Association of Teachers of Mathematics. I've got a hypothesis that says three times around your head is the same as your height. So I've got some representations of people that I'm going to test this theory on. So I measure around the head of my wooden person and it measures 9.7. And I record that on my table. Three times that head measurement would be 29.1 cm. So now I want to know the height of the person and my wooden person has a height of 31 cm. I'm going to repeat this and measure the head and height of my other people and record these on my table. Here is the data represented graphically with axes of three times around your head and the measured height. This is a very small sample of data using any representations of people. You can extend the sample to include real people, for example friends and family members. Here is a different graph looking at the difference between three times around your head and the measured height. The wooden person is smaller by a difference of 1.9. The fact that it's smaller means that what we're going to do is put across here. So the point is plotted at 29.1 and negative 1.9. And now I'm going to plot the other differences. Use the data you collect and any graphs that you generate to help you draw any conclusions about the hypothesis. Three times around your head is the same as your height.