## Monday, 28 May 2012

### The whole world sitting in Norfolk

Problems involving very large numbers sometimes have surprising results. I was thinking recently about how large an area you would need for the entire population of the world to sit down in. Could you get everyone sitting comfortably on an upright chair in an area the size of England, for example?

The room required for one person sitting on an upright chair is about 1 metre by 0.75 metres, which gives an area of 0.75 square metres. The population of the world is about 7.016 billion (7.016 × 10⁹). So we need a total area of approximately 7.016 × 0.75 × 10⁹ = 5.262 × 10⁹ square metres.

Here in the rural county of Norfolk we like to use old-fashioned acres for land area. An acre is about 4047 square metres. So to seat the population of the world we require 5.262 × 10⁹ ÷ 4047 = 1.3 × 10⁶ acres (1.3 million acres).

Guess what the area of Norfolk is? Yes, it's about 1.3 million acres! So, there you go. You could seat the entire population of the world in an area the size of Norfolk.

Does that surprise you? It did me.