Hi, I have been given a random set of data. 10 numbers. 121 123 125 100 123 123 101 146 122 140 The question says. 1. Calculate the average of the data... No problem I can do that, my answer is 122.4 2. Determine the uncertainty for the average value. < This is the part that blows my mind. There are literally hundreds of methods for this and I am not sure what to use... My working out so far is as follows: Using the information in this link. http://virgo-physics.sas.upenn.edu/uglabs/lab_manual/Error_Analysis.pdf It says. The uncertainty in the each measurement is (Max-min)/2 The uncertainty in the the average = uncertainty in each measurement/(sqrt(N)) which is 23/(sqrt10) = 7.27 or 7. answer to the whole question = 122 +/- 7 Am I thinking about this correctly? or missing it completely?