(12C Platinum) Internal Precision Test

[EdS2]

It might be interesting to refer to some calculations in Mathematics Written in Sand, by William Kahan. See especially from Page 15, "A Penny for your Thoughts" which is a FVM problem with very large n.

Notably, the HP12C, although returning the same value in the forward direction, comes up with a slightly less accurate answer than 4 other HP models when recalculating i.

Edit: see also this post for the example.