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Re: Order of magnitude

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Title: RE: Order of magnitude
     The Richter scale is based on the equivalent energy in tons of TNT.  So a 7 on the Richter scale means 1X10^7 tons of TNT.
-----Original Message-----
From: Paul Meyer <PMeyer(--nospam--at)>
To: 'seaint(--nospam--at)' <seaint(--nospam--at)>
Date: Monday, September 13, 1999 10:22 AM
Subject: RE: Order of magnitude

In Science, order of magnitude is just that, which power of ten are we involved with?  Are there 5, 50 or 500 bugs on my windshield?

In financial estimates for projects there are four levels of estimate:

Order of magnitude estimate or "opportunity study" plus 30 or minus 40 percent.
Pre-feasibility estimate:  plus or minus 20 to 25 percent
Feasibility estimate:  plus or minus 10 percent:
Construction estimate/budget:  plus or minus 5 percent.