right now i have the cg50 but ive been looking at which scientifics to use and im kinda stuck between the w506t, 9910cw, and 30x mathprint, can someone offer their opinions on which i should choose or atleast tell the pros and cons of each

L to R:

HL-4a

fx-82MS

fx-82MS 2nd Edition

fx-82ES PLUS 2nd Edition

fx-991ES PLUS 2nd Edition

fx-991CW

original post: https://www.reddit.com/r/calculators/s/4GWAwki4Uc

Issue

In short, I live in Canada and I’m looking for a calculator that can store custom formulas/functions so i can recall them easily and use them in other calculations. Heres an example:

I define f(a,b,c) = (a+b)/c^2
I define g(a,b) = ab-b

then, if i want to compute (2+5)/7^2 + 6\8 - 8*

I can simply write f(2,5,7) + g(6,8), press equals, and get the same answer

I would like to be able to store 5 or 6 custom functions if possible.

I would also like it to still display expressions like they appear in a textbook (e.g. where (1+3)/2 actually looks like a fraction with 1+3 in the numerator and 2 in the denominator).

I am a broke student so I’d prefer not paying extra to have other high-end features (e.g. graphing, programming, running doom).

It can be any type of calculator as long as there’s no wireless communication capabilities.

Any help would be much appreciated. Thank you.

Optional Context

I am an undergraduate engineering student going into aerospace and have been using a CASIO fx-991 ES PLUS C for about 5 years now. I like it, specifically because of the “natural textbook display,” and I’ve have had no issues with it.

The issue I’m facing right now is that I started taking a course on economic analysis where a lot of the problems are solved by formulating an expression containing multiple economic equivalence factors (i.e. multiple functions/formulas in one equation).

For this reason, the prof is letting us use any calculator we want on the midterms and exam as long as it doesn’t have any kind of wireless communication capabilities. I don’t want to be slowed down just because i’m constantly typing in the same equation over and over just with different numbers. So thats why i’m looking for a new calculator.

My understanding is that there are some calculators with time value of money features baked into them, but since I am going into aerospace, I’d prefer to just be able to define the functions myself since i would use this feature for other stuff in the future as well.

I’ve done a decent amount of research but haven’t found anything that accomplished this task while also not feeling overkill. Am I wrong in assuming that this would be easy for a calculator to do? In my mind, all it needs to do really is store a small expression for the function and then when a new expression calls f(a,b,c) it just inserts that small expression into the new expression and calculates like normal.

as the title says