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.
FBF = Flashback Friday. #FBF is an acronym primarily used on Instagram, Facebook, Twitter, and Tumblr that stands for Flashback Friday. Users typically use the tag on photos of moments in their past, like last yearâs vacation or a childhood friend.
The FIRM is the most common map and most communities have this type of map. At a minimum, flood maps show flood risk zones and their boundaries, and may also show floodways and Base Flood Elevations (BFEs). The FBFM is a version of a flood map that shows only the floodway and flood boundaries. The FBFM is no longer produced; current FIRMs include all of this information. The FHBM is an older version of a flood map and is based on approximate data.