# 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 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.

2. ### Simple as Pi

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

Most people’s first slice of Pi is at school where it is generally made palatable as either 3.14 or the fraction 3 1/7. The memory of this number may be fuzzy for those propelled through their Maths GCSE by the power of Casio (where Pi was reduced to a button on the bottom row of the calculator), but the likelihood is they still recall that romanticised notion of a number whose decimal places randomly go on forever. At its simplest, Pi is the ratio of the circumference of a circle to its diameter. At its most complex, it is an irrational number that cannot be expressed as the ratio of two whole numbers and has an apparently random decimal string of infinite length.

3. ### Simple as Pi

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

Most people’s first slice of Pi is at school where it is generally made palatable as either 3.14 or the fraction 3 1/7. The memory of this number may be fuzzy for those propelled through their Maths GCSE by the power of Casio (where Pi was reduced to a button on the bottom row of the calculator), but the likelihood is they still recall that romanticised notion of a number whose decimal places randomly go on forever. At its simplest, Pi is the ratio of the circumference of a circle to its diameter. At its most complex, it is an irrational number that cannot be expressed as the ratio of two whole numbers and has an apparently random decimal string of infinite length.