Calculators I actually use.

[AnnoyedOne]

(12-12-2024 08:58 PM)John Garza (3665) Wrote:  H.MS+ and H.MS- are used to directly add/subtract time without having to convert to decimal hours...

I'd never heard of those functions before but you're right.

Quote:Time calculations could be done directly with the H.MS+ and - functions, or times could be converted to/from decimal hours.

https://www.hpmuseum.org/hp55.htm

Interesting.

As for the "hard" method I've always owned a calculator with ->H and ->H.MS functions I'm lazy.

At the time I purchased a HP-15C the HP-41C was about 3x the price and the base calculator seemingly had less functions. So...

A1

PS: FYI reading p96 (p100 in the PDF) of

HP-67 Owner's Handbook and Programming Guide (00067-90011, Rev. E, 10-78)

in the section "Adding and Subtracting Time and Angles" explains the H.MS+/H.MS- functions very well.