If you are looking forward towards calculating the Standard Deviation and Standard Error of the Mean in Excel, please check this article.

Basically they calculated the size of the Earth, distance and size of the moon and distance and size of the sun. The value obtained for the distance to the sun was a bit off, but still a bang up ...

Let me just write down a more sophisticated way of finding the uncertainty of a calculated quantity (often called propagation of error). Suppose I want to calculate something, say f.