I was able to certify all these computations using calculators I found on the Internet. If there is anything that needs calculating, no matter how arcane the subject, there is a free calculator out there to help crunch the numbers. Some results are interesting but of questionable use. I know I was born on a Thursday, under the sign of the Earth Dragon during year 4566 of the Chinese calendar. And my Social Security number was issued in Rhode Island and my numerology numbers are 6 for destiny and 1 for challenge - even though I haven't the foggiest idea what they mean.
Most calculators are practical.
For example, if I had an airplane and wanted to fly from Barnstable to Syracuse, there is a calculator that will measure the great circle distance for me, do weight and balance calculations, and tell me how much fuel I would need for certain wind and temperature conditions. There are calculators to help me figure out if a reverse mortgage is a good idea, and there are dozens of sponsored calculators for financial dealings ranging from mortgages to money market yields. Of course it helps to look closely at the sponsor, just in case the numbers may be skewed in a certain direction. The simplest way to find a specific calculator is to crank up an Internet search engine and ask for one by type. But if you are really serious about your calculations, visit Martindale's Web site on calculators.