# The Golden Ratio

Episode three of Five Numbers, the BBC radio series presented by Simon Singh.

Divide any number in the Fibonacci sequence by the one before it, for example 55/34, or 21/13, and the answer is always close to 1.61803. This is known as the Golden Ratio, and hence Fibonacci’s Sequence is also called the Golden Sequence. Unlikely though it might seem, this series of numbers is the common factor linking rabbits, cauliflowers and snails.

## Possibly related…

1. ### The Number Four

Episode one of Another Five Numbers, the BBC radio series presented by Simon Singh.

Simon Singh’s journey begins with the number 4, which for over a century has fuelled one of the most elusive problems in mathematics: is it true that any map can be coloured with just 4 colours so that no two neighbouring countries have the same colour? This question has tested some of the most imaginative minds — including Lewis Carroll’s — and the eventual solution has aided the design of some of the world’s most complex air and road networks.

2. ### Infinity

Episode five of Five Numbers, the BBC radio series presented by Simon Singh.

Given the old maxim about an infinite number of monkeys and typewriters, one can assume that said simian digits will type up the following line from Hamlet an infinite number of times.

3. ### A Countdown to Zero

Episode one of Five Numbers, the BBC radio series presented by Simon Singh.

What’s 2 minus 2? The answer is obvious, right? But not if you wore a tunic, no socks and lived in Ancient Greece. For strange as it sounds, ‘nothing’ had to be invented, and then it took thousands of years to catch on.