I'm pretty good at math in my head, I thank being a cashier for that.

While I can't use a slide rule (but I can do long division), I did use it once...

Had a chemistry final in college. Professor said no calculators. I promptly borrowed my dad's slide rule, sat in the front rule, and fiddled around like mad trying to [censored] off the teacher ( I wasn't fond of her "office hours" as her answers tended to be "read the book." B!%ch. I'm still pissed, 15 years later)

Yep. And calc. Taking roots I can't remember how to do by hand, but that and working a slip stick is probably about all I can't do. Give me ten minutes to remember how and I can probably even work out the trig values long hand to. :P

I had calc and trig and stats profs in college who yelled at you if you used a calculator, or pen.

Heck, I've even got a CRC Math Tables book, and I've used most chapters in it.

The yellow slide rule is a Pickett Simplex Trig N902-ES (ver.1) with K, A, B, T, S, CI, C, D & L scales. Fortunately, it has instructions printed on the back so that I don't have to find a manual if I need to use it. I picked it up at Goodwill for a buck.

The clear ruler thingy is one of those "as seen on TV" jobbers my mom picked up many years ago. It's got several geometry & trigonometry formulas on it.

I forgot the E6-B or the CPU-26A/P and the plotter along with the sectional.

Now, if only I had a sextant.....

Now there's a lost skill.

I have a slide rule and a 1968 CRC Math (older than me) right here. I can do long division all day. Trying to get my kids into it.

Just don't ask me to work out anything on a Smith chart.

That's OK as most folks have trouble enough with real numbers let alone the imaginary numbers on the z plane.

Smith Chart - shudder