# A python curls up to touch the tip of its own tail with its nose, forming the shape of a circle.

A python curls up to touch the tip of its own tail with its nose, forming the shape of a circle.

The python is 2.6 pi (2.6π) meters long.

What is the radius r of the circle that the python forms?

Obviously, this is not about the programming language. Someone was searching for this, well, lots of people were, so why not answer it?

Snakes are scary. Instead of thinking of it as a snake, assume it’s just the circumference of a circle - the length of the line that draws the circle. Let’s find some formulas that connect the circumference with the radius!

According to Wikipedia (or rather, according to Archimedes, in 250BC, long before my time), the ratio of circumference to diameter (twice the radius) of a circle is “greater than 3 10/71 and less than 3 1/7” (or simpler, just “pi”, which is how to write the symbol π – who comes up with this stuff? It doesn’t even look like a cake).

Now we have: C = π d, or (with d = 2 r):  C = 2 π r.

Changing that around: r = C / 2 π

So with our value of C = 2.6π meters, that gives us:

r = 2.6π/2π = 2.6/2, so **r = 1.3 meters **

There you have it.

For the second part of the question: please explain in the comments below how you would measure the length of a python with the accuracy of pi.