[tzs]

One can make a good argument that the "why" of math is really the only reason to teach it as a standard subject required for everyone, at least beyond just elementary arithmetic.

We like to pretend that all kinds of jobs require knowing algebra and geometry, but no, but that is greatly exaggerated.

What you learn when you study those subjects that you have a decent chance of actually using on the job is how to reason.

There were a couple of interesting essays on this point by Underwood Dudley.

One is called "What is Mathematics For?" (which he admits is click-bait, and it should really be called "What is Mathematics Education For") from the May 2010 "Notices of the AMS" [1].

The other is called "Is Mathematics Necessary?" [2], which I believe is an earlier, shorter version of the what later became the AMS article.

[1] https://www.ams.org/notices/201005/rtx100500608p.pdf

[2] http://www.public.iastate.edu/~aleand/dudley.html