As used in airline computers I would expect.

I bought this 4kB. Computer, a Sharp PC-1247 a long time ago from Radio Shack and I haven't seen anything as good in programming Basic since. I have two programmes on it now, one as the photo shows, (see Chatterbox. )measures distance between two places* and the other, not shown, the length of a parabola .[I am up north at present and the cottage was left in near perfect shape by the last guests]

Where can I find a Basic Programme to download to Excel, I wonder?

*Calculating the distance between Toronto and Port Charlotte using Latitude and Longitude given in degrees and minutes, you have to change them to decimals of a degree before calculating the distance. You can use the formula given, bearing in mind that latitude and longitude are from my Toronto home and the bungalow in Port Charlotte (from a GPS reading). If you use the Sharp computer, ensure it is on "Run" : not "Pro" (which is used only for entering a Basic programme)

Enter Def A and Latitude Start will appear on the little screen. Then plug in the Latitude and press Enter. Next will appear Longitude Start, then the other two will follow - I don't have to spell it out for you. The answer is in miles, and it says as much on the tiny screen.

For places East of Greenwich or South of the equator, like Australia, put a minus sign before the Latitude or Longitude.Do this both on a calculator (pen and paper method) or on a computer.

I did write something similar to this many years ago, but even if you don't have a computer programme in Basic you can take the cosine and sine of a number on a calculator, and the arcsine and arccos of your figures to obtain Miles as illustrated using the formula.I have checked my answers using a calculator and the computer and I am relieved to find they both are the same 1166 miles