What ratio of two integers provides the value of the constant pi to 100 digits accuracy?
One possible answer is 314159265358979323846264338327950288419716939937510 5820974944592307816406286208998628034825342117068/10^99
Yes 200m is larger than 20000mm. 1m=1000mm therfore 20000mm=20m.
What is the ratio as a fraction?
It is simply another way of representing the number.
The ratio 2:5 is just 2/5.
This is Dalton's law of definite proportions. It sounds esoteric, but it just means that the same substance always has the same formula.