Say we have a bunch of numbers like 9, 2, 5, 4, 12, 7, 8, 11. To calculate the standard deviation of those numbers: 1  1. 2  Work out the Mean (the simple average of the numbers). 3  2. Then for each number: subtract the Mean and square the result. 4  3. Then work out the mean of those squared differences.5  4. Take the square root of that and we are done!o calculate the standard deviation of those numbers: 1  1. 2  Work out the Mean (the simple average of the numbers). 3  2. Then for each number: subtract the Mean and square the result.
Best Answer: The .925 does mean sterling silver and the FB may be a Hallmark. You did not state what is on the medallion so I don't know where it was made. On some silver items the FB stands for Franz Bibus a Czech silversmith.
FNR-Frame Noise Reduction: used to eliminate fine noises from blu-ray discs. BNR-Block Noise Reduction: used to eliminate mosiac like noises.MNR-Mosquito Noise Reduction: no idea as the abbreviation is itself so confusing. gold ring will have the gold content inscribed inside. It may  also have the manufacturer's mark inside. 5C would be the  manufacturer's mark.