I endured three semesters of calculus and one of differential equations, but never used any of it. I used algebra and trig fairly often in the construction game, though.
I’m an insurance actuary. I do math all day, but most of it is simple–I add, subtract, multiply, divide, and occasionally raise a number to a power. However, to understand and explain the results of those operations, and to determine whether models are working correctly, requires a fairly sophisticated understanding of probability and statistics, and sometimes simple calculus.
I am always amazed at how little math my colleagues know.
It comes up from time to time. In the field I work, I am actually a rarity…a statistician with a masters in math. I have done this for over 20 years and only twice have I met someone doing what I do that had a math degree.
These people are not idiots…many are very smart. Ph.D’s galore etc etc. and they know much about statistics and how to apply it. It is just that their degrees are not in math. There are also many programs out there to allow you to do things and not learn the underlying math.
So, you run across situations where you need to do things ‘by hand’ (i.e. in Excel). A colleague called me and said someone was complaining that her perceptual maps needed to be rotated. Usually they need to be rotated by some multiple of 90 degrees and this is easily done. However, this client needed something rotated by approximately 50 degrees.
So, I told her…rotate it in Excel. How? Use Trig!. A few hours go by and she emails me again for more help. I write up what I thought was a simple explanation…and she calls. I have to share a computer screen and show her and find out she never had Trig.
Well, she never needed it. Probably won’t ever need to again. She also found a program that will do it for her if she ever needs to again…she won’t have to do it ‘by hand’ ever again.
Another time someone wanted to find the rate of change of a model at a point and was guessing. Just take the derivative…the equation is right there! Huh…what?! You guessed…little to no Calculus in his background.
Make no mistake, these people are good at their jobs and very smart. However, sometimes you need the ‘intuition’ that comes with having a background in math. I have noticed that while I am surrounded by Ph.D’s that I am the one that has come up with new techniques and still am while they do not. 
Highest math was college level calculus II and statistics I.
I work in a lab. I do various calculations all day long. Most days it is just dilutions, making solution (make a 10 mM solution of a substance with a MW of 371.2, you have 1 mg of the compound or dilute a protein solution of 212 ug/mL to 50, 25, 12.5 and 6.25 pg/mL for use in an experiment).
Once to twice a week I have to do more complex calculations for enzyme kinetics or other higher order math equations. Thankfully, I have software that does enzyme kinetics for us, I just plug in the relevant numbers. For the other stuff, I have an excel macro written and again I just plug the relevant numbers in (but I did have to write the macro and understand the equations in the first place).
I’m working on a PhD in statistics, so pretty much everything I ever do is mathematical to some degree.
I went up through Calc in high school, and I’ve never used anything more advanced than basic algebra or geometry in the 40 years since then.
Physicist and Engineer, so I got through alculus, differential equations, Group Theory, lots of things useful for calculation and problem-solving (least squares, quadrature, various transforms, special funcytions, etc.) along with odd stuff in other areas – Boolean algebra, Karnaugh maps, and the like.
I read math books for fun and in bed before going to sleep, which drives my wife nuts. So I’ve read some in number theory and odd geometry. Two utterly fascinating books are A Dictionary of Curious and Unusual Numbers and a Dictionary of Curious and Interesting Geometry, buth edited by David wells and published by Penguin.
I’m surprised to find that my fellow techies often do not use math regularly, especiaaly those into computers and IT. I still use quite a range of math practically every day. My daughter, who does well in high school math, but has to work at it, still asks me “what good is this going to be for me in everyday life?” For me the answer is obvious, but if she doesn’t go into science or engineering, I’m not sure, beyond the fact that it teaches her problem solving and persistence.
I got some AP credits in math for college and took one math course in college (advanced theoretical calculus). That was 35+ years ago. These days all I do (occasionally) is add, subtract, multiply and divide, and to do that I often use a calculator. It’s too bad, I liked math but am not motivated to keep up with it as a hobby, so I’ve lost most of what I knew.
I’m a solar physicist and teach college-level physics courses; I do a lot of math on a regular basis! Right now, the work related math involves statistics, calculus and more statistics. I’m currently teaching math methods in physics, so I spend three days a week teaching students how to take pure mathematics and apply it to physics, physical systems and what the pure math represents.
Well, OK then.
The highest level of maths that I’ve passed an exam in is Honours-level mathematical computer science. (“Honours”, in the South African system, is somewhere between final-year Bachelors and graduate coursework.) Since then I’ve been working on a thesis, which counts as “training”, I suppose.
Obviously in working on my thesis, the most advanced maths I do is the maths that I am simultaneously learning. I teach first- and second-year students, so I regularly use maths from that level - principally logic & set theory, linear algebra, multivariate calculus, abstract algebra, and real analysis.
Outside of studying and teaching, I have used some trigonometry for woodworking, and more complicated trig for some amateur work I do on GIS software. I’ve occasionally used some calculus to solve real-world optimization problems but I can’t remember now what they were.
I do finance, it’s mostly arithmetic these days. The trick is more in knowing what you need to subtract or divide from what and how to present it.
I was building a trellis last week, and actually had to breakout out some trigonometry to know what angle to set my saw at to match the slope I wanted on the supports.
I do research in Machine Learning, so I end up doing tons of math on occasion, and little math on other occasions. One example is when I was emulating naive kinematic physics with a finite state machine (long story, there was a point to all this), I had to do a lot of calculations by hand, albeit low level math, nothing more complicated than super basic integrals.
That said, I also do a lot of theoretical proofs, automata theory and whatnot. The “math” component isn’t more than sets, discrete math, and the occasional algebra, but I think it’s in the “intermediate level” category (where I consider calculatory math as more “low level” and hugely abstract meta-maths like abstract algebra as more “high level”).
However, I’m starting research into virtual reality too, which I get to have fun with trying to triangulate people’s positions in 3D space with a camera array, and then convert that and do things like mirror their position in a realtime 3D rendering program. It’s honestly just linear algebra, but it’s a LOT of linear algebra.
Edit: Trig is my least favorite math though, I sucked at it in high school. I can do a lot of cool things with trig, a calculator, and an identity reference sheet, but I never was good at memorizing cosine of what radians is what, or identities. Those always seemed like busywork to me.
I was captain of the math league team in high school and got all A’s through senior calculus. Never took any college-level math except for a course in statistics.
In my job I mostly do basic math stuff - budgets, date calculations, a lot of salary/pay calculations but it’s all addition, subtraction, division for the most part. Occasional basic algebra but that’s about it. My nieces now ask me for help with their trig homework but the only way I can help them is by reading along in the book with them - I don’t remember any of that stuff anymore on my own.
Editor. The odd bits of arithmetic, and mostly addition and subtraction at that.
A fair amount. I’m working on a biology PhD. Every day there’s a lot of quick mental math for dosing or mixing up reactions. Sometimes that’s more than I can do in my head and I do some basic algebra with pen and paper and calculator. Then, once I have some data, I have to do some analysis and statistical testing. That ranges from "Excel, do me a t-test " to implementing some more complicated statistics in R.
Right now I’m taking a course on the statistical theory of DNA sequence analysis. The prof has everyone up writing on whiteboards (eight at a time) as he walks the class through the material.
Previously, I had calc through diff eq, but I was definitely struggling at the end…
Same here.
I work in market research. In business school, I had to take two semesters of calculus (though it was “business calc”, which was apparently dumbed-down compared to the version that science majors took), and three semesters of statistics.
I don’t do a whole lot in my job with true math (beyond addition and multiplication), but I do quite a lot with statistics, so I suppose that counts.
Machinist here, I use quite a bit of trig and geometry but it varies. If I am at home, I have been known to cheat for the trickier stuff and draw it up in AutoCAD and take dimensions rather than doing the math.:o I have had through Calc III but lost most of it. I really should take some refresher courses.
I work in marketing. I use math through algebra every day, many times a day. I did have to learn calculus to understand some of the economic concepts we used in school. I don’t have to replicate that math now, but I still need to understand the concepts. And we’re heavy in stats. I need to do my own statistical analysis plus be able to understand (if not replicate) the stats our market researchers throw our way.
However, having a good understanding of how numbers describe data is more important than being able to do the calculations. At a basic level, I need to know what the various averages and distributions tell me and what they don’t tell me. At a very simple level, I need to know why getting an average rating of 3 in a review can mean different things depending on whether you get mostly 3’s or whether you get a lot of 1’s and a lot of 5’s but few scores in the middle. What you do in each situation is going to be very different.
As a result, even if I never use that second year calculus class, I’m damned glad I took as many math classes as I did. I like the fact that I’m working well within my comfort zone with numbers. It’s when I’m pushing the edge of my understanding that I start to get a bit nervous about whether I have the familiarity to know what the numbers mean.
I work in image processing, which straddles the line between math, computer science, and electrical engineering (all my degrees are from ECE departments, fwiw).
On a daily basis I use geometry, calculus, algebra, and statistics. If I’m not doing math of some sort, I’m programming so that the math I’ve selected can be applied to a particular problem.