HP 10bii+ Margin/Markup bug

[Gamo]

Seem like HP use the Equations Solver for when input two knowns variables
will give result to the remaining two unknown variables.
But will not work for all cases espectually when input CST, MAR → MU, PRC

My program for the HP-12C the algorithm use is when one of the MU or MAR is known
go ahead and convert it then calculate the remaining formula. This method is effective
when user run through the input in series thinks of this like the Ohm's Law program.
User input either in the store register or input all in the stacks and put in zero for the varibles
that need to be solve.

For example:
Cost = 0 // Unknown
Price = 10
Markup = 25
Margin = 0 // Unknown

The Markup is known then convert to Margin
Now got result on both Markup and Margin calculate the remaining formula.

Remark:
But when I try to program this Pricing Calculations to like HP-11C it is very complicated
to imprement all the neccessary situations for all cases with Cost, Price, Markup and Margin.
Took me a long time to get it right and it need to use the "Flags" function extensively in program.


Gamo